List of Edited Articles
Recently published articles handled as primary editor:
Recently published articles handled as primary editor:
Jeongsu Pyeon, Soon Mo Park, Juri Kim, Jeong-Hwan Kim, Yong-Jin Yoon, Dong Ki Yoon, Hyoungsoo Kim
Plasmonic metasurfaces of cellulose nanocrystal matrices with quadrants of aligned gold nanorods for photothermal anti-icing
In: Nature Communications, vol. 14, no. 8096, 2023, (Cellulose nanocrystals are very attractive as a matrix material for plasmonic nanoparticles, but controlling particle orientation for patterning is challenging. Here, the authors prepare annular ring patterns with quadrants of aligned gold nanorods for photothermal applications.).
Cellulose nanocrystals (CNCs) are intriguing as a matrix for plasmonic metasurfaces made of gold nanorods (GNRs) because of their distinctive properties, including renewability, biodegradability, non-toxicity, and low cost. Nevertheless, it is very difficult to precisely regulate the positioning and orientation of CNCs on the substrate in a consistent pattern. In this study, CNCs and GNRs, which exhibit tunable optical and anti-icing capabilities, are employed to manufacture a uniform plasmonic metasurface using a drop-casting technique. Two physical phenomena—(i) spontaneous and rapid self-dewetting and (ii) evaporation-induced self-assembly—are used to accomplish this. Additionally, we improve the CNC-GNR ink composition and determine the crucial coating parameters necessary to balance the two physical mechanisms in order to produce thin films without coffee rings. The final homogeneous CNC-GNR film has consistent annular ring patterns with plasmonic quadrant hues that are properly aligned, which enhances plasmonic photothermal effects. The CNC-GNR multi-array platform offers above-zero temperatures on a substrate that is subcooled below the freezing point. The current study presents a physicochemical approach for functional nanomaterial-based CNC control.
Ziqing Zhang, Jinrun Dong, Yibo Yang, Yuan Zhou, Yuang Chen, Yang Xu, Jiandong Feng
Direct probing of single-molecule chemiluminescent reaction dynamics under catalytic conditions in solution
In: Nature Communications, vol. 14, no. 7993, 2023, (Research into the dynamics of chemical reactions at the single-molecule level is a pivotal undertaking. Here, the authors present a direct investigation of the chemiluminescent reaction dynamics of single molecules in solution, providing spatiotemporally resolved insights into chemical reactions.).
Chemical reaction kinetics can be evaluated by probing dynamic changes of chemical substrates or physical phenomena accompanied during the reaction process. Chemiluminescence, a light emitting exoenergetic process, involves random reaction positions and kinetics in solution that are typically characterized by ensemble measurements with nonnegligible average effects. Chemiluminescent reaction dynamics at the single-molecule level remains elusive. Here we report direct imaging of single-molecule chemiluminescent reactions in solution and probing of their reaction dynamics under catalytic conditions. Double-substrate Michaelis–Menten type of catalytic kinetics is found to govern the single-molecule reaction dynamics in solution, and a heterogeneity is found among different catalyst particles and different catalytic sites on a single particle. We further show that single-molecule chemiluminescence imaging can be used to evaluate the thermodynamics of the catalytic system, resolving activation energy at the single-particle level. Our work provides fundamental insights into chemiluminescent reactions and offers an efficient approach for evaluating catalysts.
Shigeki Kawai, Orlando J. Silveira, Lauri Kurki, Zhangyu Yuan, Tomohiko Nishiuchi, Takuya Kodama, Kewei Sun, Oscar Custance, Jose L. Lado, Takashi Kubo, Adam S. Foster
Local probe-induced structural isomerization in a one-dimensional molecular array
In: Nature Communications, vol. 14, no. 7741, 2023, (Achieving unit-by-unit isomerization within a molecular array poses a significant challenge in chemistry. Here, the authors demonstrate tip-induced stereoisomerization of dehydroazulene and diradical units in three-dimensional organometallic compounds on Ag(111).).
Synthesis of one-dimensional molecular arrays with tailored stereoisomers is challenging yet has great potential for application in molecular opto-, electronic- and magnetic-devices, where the local array structure plays a decisive role in the functional properties. Here, we demonstrate the construction and characterization of dehydroazulene isomer and diradical units in three-dimensional organometallic compounds on Ag(111) with a combination of low-temperature scanning tunneling microscopy and density functional theory calculations. Tip-induced voltage pulses firstly result in the formation of a diradical species via successive homolytic fission of two C-Br bonds in the naphthyl groups, which are subsequently transformed into chiral dehydroazulene moieties. The delicate balance of the reaction rates among the diradical and two stereoisomers, arising from an in-line configuration of tip and molecular unit, allows directional azulene-to-azulene and azulene-to-diradical local probe structural isomerization in a controlled manner. Furthermore, our theoretical calculations suggest that the diradical moiety hosts an open-shell singlet with antiferromagnetic coupling between the unpaired electrons, which can undergo an inelastic spin transition of 91 meV to the ferromagnetically coupled triplet state.
Peihui Li, Songjun Hou, Qingqing Wu, Yijian Chen, Boyu Wang, Haiyang Ren, Jinying Wang, Zhaoyi Zhai, Zhongbo Yu, Colin J. Lambert, Chuancheng Jia, Xuefeng Guo
The role of halogens in Au–S bond cleavage for energy-differentiated catalysis at the single-bond limit
In: Nature Communications, vol. 14, no. 7695, 2023, (Investigation of the reaction process at the single-bond interface is key to understanding the catalytic reaction mechanism. Here, the authors develop a STM-BJ method to monitor the catalytic process from the perspective of single-bond energy.).
The transformation from one compound to another involves the breaking and formation of chemical bonds at the single-bond level, especially during catalytic reactions that are of great significance in broad fields such as energy conversion, environmental science, life science and chemical synthesis. The study of the reaction process at the single-bond limit is the key to understanding the catalytic reaction mechanism and further rationally designing catalysts. Here, we develop a method to monitor the catalytic process from the perspective of the single-bond energy using high-resolution scanning tunneling microscopy single-molecule junctions. Experimental and theoretical studies consistently reveal that the attack of a halogen atom on an Au atom can reduce the breaking energy of Au−S bonds, thereby accelerating the bond cleavage reaction and shortening the plateau length during the single-molecule junction breaking. Furthermore, the distinction in catalytic activity between different halogen atoms can be compared as well. This study establishes the intrinsic relationship among the reaction activation energy, the chemical bond breaking energy and the single-molecule junction breaking process, strengthening our mastery of catalytic reactions towards precise chemistry.
Jacques Doumani, Minhan Lou, Oliver Dewey, Nina Hong, Jichao Fan, Andrey Baydin, Keshav Zahn, Yohei Yomogida, Kazuhiro Yanagi, Matteo Pasquali, Riichiro Saito, Junichiro Kono, Weilu Gao
Engineering chirality at wafer scale with ordered carbon nanotube architectures
In: Nature Communications, vol. 14, no. 7380, 2023, (Methods for generating macroscopic chiral matter struggle with limited scalability. Here, the authors show two vacuum filtration methods - twist stacking and mechanical rotation - to align carbon nanotubes into chiral structures at wafer scale with tunable circular dichroism.).
Creating artificial matter with controllable chirality in a simple and scalable manner brings new opportunities to diverse areas. Here we show two such methods based on controlled vacuum filtration - twist stacking and mechanical rotation - for fabricating wafer-scale chiral architectures of ordered carbon nanotubes (CNTs) with tunable and large circular dichroism (CD). By controlling the stacking angle and handedness in the twist-stacking approach, we maximize the CD response and achieve a high deep-ultraviolet ellipticity of 40 ± 1 mdeg nm−1. Our theoretical simulations using the transfer matrix method reproduce the experimentally observed CD spectra and further predict that an optimized film of twist-stacked CNTs can exhibit an ellipticity as high as 150 mdeg nm−1, corresponding to a g factor of 0.22. Furthermore, the mechanical rotation method not only accelerates the fabrication of twisted structures but also produces both chiralities simultaneously in a single sample, in a single run, and in a controllable manner. The created wafer-scale objects represent an alternative type of synthetic chiral matter consisting of ordered quantum wires whose macroscopic properties are governed by nanoscopic electronic signatures and can be used to explore chiral phenomena and develop chiral photonic and optoelectronic devices.
Francis Schuknecht, Karol Kołątaj, Michael Steinberger, Tim Liedl, Theobald Lohmueller
Accessible hotspots for single-protein SERS in DNA-origami assembled gold nanorod dimers with tip-to-tip alignment
In: Nature Communications, vol. 14, no. 7192, 2023, (The identification of individual proteins is highly desirable in diagnostics. Here, the authors report on DNA-origami assembled dimers of gold nanorod with accessible hotspots to capture and identify single proteins from solution by SERS.).
The label-free identification of individual proteins from liquid samples by surface-enhanced Raman scattering (SERS) spectroscopy is a highly desirable goal in biomedical diagnostics. However, the small Raman scattering cross-section of most (bio-)molecules requires a means to strongly amplify their Raman signal for successful measurement, especially for single molecules. This amplification can be achieved in a plasmonic hotspot that forms between two adjacent gold nanospheres. However, the small (≈1−2 nm) gaps typically required for single-molecule measurements are not accessible for most proteins. A useful strategy would thus involve dimer structures with gaps large enough to accommodate single proteins, whilst providing sufficient field enhancement for single-molecule SERS. Here, we report on using a DNA origami scaffold for tip-to-tip alignment of gold nanorods with an average gap size of 8 nm. The gaps are accessible to streptavidin and thrombin, which are captured at the plasmonic hotspot by specific anchoring sites on the origami template. The field enhancement achieved for the nanorod dimers is sufficient for single-protein SERS spectroscopy with sub-second integration times. This design for SERS probes composed of DNA origami with accessible hotspots promotes future use for single-molecule biodiagnostics in the near-infrared range.
Vivien Walter, Dadi Bi, Ali Salehi-Reyhani, Yansha Deng
Real-time signal processing via chemical reactions for a microfluidic molecular communication system
In: Nature Communications, vol. 14, no. 7188, 2023, (The use of electronic devices to process electrical signals in molecular communications can hardly realize its potential for various applications. Here, the authors report on chemical concentration signal processing in real time and digital signal transmission over distances.).
Signal processing over the molecular domain is critical for analysing, modifying, and synthesising chemical signals in molecular communication systems. However, the lack of chemical signal processing blocks and the wide use of electronic devices to process electrical signals in existing molecular communication platforms can hardly meet the biocompatible, non-invasive, and size-miniaturised requirements of applications in various fields, e.g., medicine, biology, and environment sciences. To tackle this, here we design and construct a liquid-based microfluidic molecular communication platform for performing chemical concentration signal processing and digital signal transmission over distances. By specifically designing chemical reactions and microfluidic geometry, the transmitter of our platform is capable of shaping the emitted signals, and the receiver is able to threshold, amplify, and detect the chemical signals after propagation. By encoding bit information into the concentration of sodium hydroxide, we demonstrate that our platform can achieve molecular signal modulation and demodulation functionalities, and reliably transmit text messages over long distances. This platform is further optimised to maximise data rate while minimising communication error. The presented methodology for real-time chemical signal processing can enable the implementation of signal processing units in biological settings and then unleash its potential for interdisciplinary applications.
Marti Checa, Addis S. Fuhr, Changhyo Sun, Rama Vasudevan, Maxim Ziatdinov, Ilia Ivanov, Seok Joon Yun, Kai Xiao, Alp Sehirlioglu, Yunseok Kim, Pankaj Sharma, Kyle P. Kelley, Neus Domingo, Stephen Jesse, Liam Collins
High-speed mapping of surface charge dynamics using sparse scanning Kelvin probe force microscopy
In: Nature Communications, vol. 14, no. 7196, 2023, (Dynamic mapping of charge motion across multiple length- and timescales is essential for understanding a variety of phenomena. Here, the authors introduce sparse scanning KPFM, which enables fast nanoscale charge mapping at 3 frames per second to track ion migration.).
Unraveling local dynamic charge processes is vital for progress in diverse fields, from microelectronics to energy storage. This relies on the ability to map charge carrier motion across multiple length- and timescales and understanding how these processes interact with the inherent material heterogeneities. Towards addressing this challenge, we introduce high-speed sparse scanning Kelvin probe force microscopy, which combines sparse scanning and image reconstruction. This approach is shown to enable sub-second imaging (>3 frames per second) of nanoscale charge dynamics, representing several orders of magnitude improvement over traditional Kelvin probe force microscopy imaging rates. Bridging this improved spatiotemporal resolution with macroscale device measurements, we successfully visualize electrochemically mediated diffusion of mobile surface ions on a LaAlO3/SrTiO3 planar device. Such processes are known to impact band-alignment and charge-transfer dynamics at these heterointerfaces. Furthermore, we monitor the diffusion of oxygen vacancies at the single grain level in polycrystalline TiO2. Through temperature-dependent measurements, we identify a charge diffusion activation energy of 0.18 eV, in good agreement with previously reported values and confirmed by DFT calculations. Together, these findings highlight the effectiveness and versatility of our method in understanding ionic charge carrier motion in microelectronics or nanoscale material systems.
Zhiwen Jiang, Carine Clavaguéra, Changjiang Hu, Sergey A. Denisov, Shuning Shen, Feng Hu, Jun Ma, Mehran Mostafavi
Direct time-resolved observation of surface-bound carbon dioxide radical anions on metallic nanocatalysts
In: Nature Communications, vol. 14, no. 7116, 2023, (Understanding the activity and selectivity of metal catalysts requires elucidating the dynamics of CO2•− radicals bound to the surface. Here, the authors use pulse radiolysis to directly observe the stabilization process of CO2•− radicals at nanoscale metallic sites from nanoseconds to seconds.).
Time-resolved identification of surface-bound intermediates on metallic nanocatalysts is imperative to develop an accurate understanding of the elementary steps of CO2 reduction. Direct observation on initial electron transfer to CO2 to form surface-bound CO2•− radicals is lacking due to the technical challenges. Here, we use picosecond pulse radiolysis to generate CO2•− via aqueous electron attachment and observe the stabilization processes toward well-defined nanoscale metallic sites. The time-resolved method combined with molecular simulations identifies surface-bound intermediates with characteristic transient absorption bands and distinct kinetics from nanosecond to the second timescale for three typical metallic nanocatalysts: Cu, Au, and Ni. The interfacial interactions are further investigated by varying the important factors, such as catalyst size and the presence of cation in the electrolyte. This work highlights fundamental ultrafast spectroscopy to clarify the critical initial step in the CO2 catalytic reduction mechanism.
Bowen Sui, Youliang Zhu, Xuemei Jiang, Yifan Wang, Niboqia Zhang, Zhongyuan Lu, Bai Yang, Yunfeng Li
Recastable assemblies of carbon dots into mechanically robust macroscopic materials
In: Nature Communications, vol. 14, no. 6782, 2023, (The assembly of nanoparticles into macroscopic materials forms the basis for various advanced material applications. Here, the authors develop macroscopic materials that are both recastable and mechanically robust, despite being composed purely of carbon dots.).
Assembly of nanoparticles into macroscopic materials with mechanical robustness, green processability, and recastable ability is an important and challenging task in materials science and nanotechnology. As an emerging nanoparticle with superior properties, macroscopic materials assembled from carbon dots will inherit their properties and further offer collective properties; however, macroscopic materials assembled from carbon dots solely remain unexplored. Here we report macroscopic films assembled from carbon dots modified by ureido pyrimidinone. These films show tunable fluorescence inherited from carbon dots. More importantly, these films exhibit collective properties including self-healing, re-castability, and superior mechanical properties, with Young’s modulus over 490 MPa and breaking strength over 30 MPa. The macroscopic films maintain original mechanical properties after several cycles of recasting. Through scratch healing and welding experiments, these films show good self-healing properties under mild conditions. Moreover, the molecular dynamics simulation reveals that the interplay of interparticle and intraparticle hydrogen bonding controls mechanical properties of macroscopic films. Notably, these films are processed into diverse shapes by an eco-friendly hydrosetting method. The methodology and results in this work shed light on the exploration of functional macroscopic materials assembled from nanoparticles and will accelerate innovative developments of nanomaterials in practical applications.
Alexander M. Bergmann, Jonathan Bauermann, Giacomo Bartolucci, Carsten Donau, Michele Stasi, Anna-Lena Holtmannspötter, Frank Jülicher, Christoph A. Weber, Job Boekhoven
Liquid spherical shells are a non-equilibrium steady state of active droplets
In: Nature Communications, vol. 14, no. 6552, 2023, (Dissipative structures are governed by non-equilibrium thermodynamics. Here, the authors describe a size-dependent transition from active droplets to active spherical shells—a dissipative structure that arises from reaction diffusion gradients. ).
Liquid-liquid phase separation yields spherical droplets that eventually coarsen to one large, stable droplet governed by the principle of minimal free energy. In chemically fueled phase separation, the formation of phase-separating molecules is coupled to a fuel-driven, non-equilibrium reaction cycle. It thus yields dissipative structures sustained by a continuous fuel conversion. Such dissipative structures are ubiquitous in biology but are poorly understood as they are governed by non-equilibrium thermodynamics. Here, we bridge the gap between passive, close-to-equilibrium, and active, dissipative structures with chemically fueled phase separation. We observe that spherical, active droplets can undergo a morphological transition into a liquid, spherical shell. We demonstrate that the mechanism is related to gradients of short-lived droplet material. We characterize how far out of equilibrium the spherical shell state is and the chemical power necessary to sustain it. Our work suggests alternative avenues for assembling complex stable morphologies, which might already be exploited to form membraneless organelles by cells.
Rutvik Lathia, Satchit Nagpal, Chandantaru Dey Modak, Satyarthi Mishra, Deepak Sharma, Bheema Sankar Reddy, Pavan Nukala, Ramray Bhat, Prosenjit Sen
Tunable encapsulation of sessile droplets with solid and liquid shells
In: Nature Communications, vol. 14, no. 6445, 2023, (Encapsulated liquids are important for several microreactor applications, including (bio)chemistry in confined spaces. Here, the authors report on oil-infused particle shells that allow control of shell thickness, stability, and permeability for applications in crystal growth and cell cultivation.).
Droplet encapsulations using liquid or solid shells are of significant interest in microreactors, drug delivery, crystallization, and cell growth applications. Despite progress in droplet-related technologies, tuning micron-scale shell thickness over a large range of droplet sizes is still a major challenge. In this work, we report capillary force assisted cloaking using hydrophobic colloidal particles and liquid-infused surfaces. The technique produces uniform solid and liquid shell encapsulations over a broad range (5–200 μm shell thickness for droplet volume spanning over four orders of magnitude). Tunable liquid encapsulation is shown to reduce the evaporation rate of droplets by up to 200 times with a wide tunability in lifetime (1.5 h to 12 days). Further, we propose using the technique for single crystals and cell/spheroid culture platforms. Stimuli-responsive solid shells show hermetic encapsulation with tunable strength and dissolution time. Moreover, scalability, and versatility of the technique is demonstrated for on-chip applications.
Eric Cereceda-López, Alexander P. Antonov, Artem Ryabov, Philipp Maass, Pietro Tierno
Overcrowding induces fast colloidal solitons in a slowly rotating potential landscape
In: Nature Communications, vol. 14, no. 6448, 2023, (Solitons are peculiar waves propagating without changing their shape. Here, the authors show that colloidal particles in a rotating optical landscape create rapidly propagating solitons, formed by particle clusters through many-body interactions.).
Collective particle transport across periodic energy landscapes is ubiquitously present in many condensed matter systems spanning from vortices in high-temperature superconductors, frictional atomic sliding, driven skyrmions to biological and active matter. Here we report the emergence of fast solitons propagating against a rotating optical landscape. These experimentally observed solitons are stable cluster waves that originate from a coordinated particle exchange process which occurs when the number of trapped microparticles exceeds the number of potential wells. The size and speed of individual solitons rapidly increase with the particle diameter as predicted by theory and confirmed by numerical simulations. We show that when several solitons coexist, an effective repulsive interaction can stabilize their propagation along the periodic potential. Our experiments demonstrate a generic mechanism for cluster-mediated transport with potential applications to condensed matter systems on different length scales.
Deepak Karna, Eriko Mano, Jiahao Ji, Ibuki Kawamata, Yuki Suzuki, Hanbin Mao
Chemo-mechanical forces modulate the topology dynamics of mesoscale DNA assemblies
In: Nature Communications, vol. 14, no. 6459, 2023, (Understanding the topological arrangement and transition dynamics of mesoscale assemblies is complicated by their molecular complexity. Here, the authors use DNA origami nanosprings to show that mesoscale helical handedness is dictated by backbone torque rather than achiral orientation.).
The intrinsic complexity of many mesoscale (10–100 nm) cellular machineries makes it challenging to elucidate their topological arrangement and transition dynamics. Here, we exploit DNA origami nanospring as a model system to demonstrate that tens of piconewton linear force can modulate higher-order conformation dynamics of mesoscale molecular assemblies. By switching between two chemical structures (i.e., duplex and tetraplex DNA) in the junctions of adjacent origami modules, the corresponding stretching or compressing chemo-mechanical stress reversibly flips the backbone orientations of the DNA nanosprings. Both coarse-grained molecular dynamics simulations and atomic force microscopy measurements reveal that such a backbone conformational switch does not alter the right-handed chirality of the nanospring helix. This result suggests that mesoscale helical handedness may be governed by the torque, rather than the achiral orientation, of nanospring backbones. It offers a topology-based caging/uncaging concept to present chemicals in response to environmental cues in solution.
Marloes H. Bistervels, Balázs Antalicz, Marko Kamp, Hinco Schoenmaker, Willem L. Noorduin
Light-driven nucleation, growth, and patterning of biorelevant crystals using resonant near-infrared laser heating
In: Nature Communications, vol. 14, no. 6350, 2023, (Natural biominerals deposit with precise spatial and temporal control, but such control is difficult to replicate artificially. Here, the authors start, steer, and stop the crystallization of biorelevant minerals by user-defined light patterns.).
Spatiotemporal control over crystal nucleation and growth is of fundamental interest for understanding how organisms assemble high-performance biominerals, and holds relevance for manufacturing of functional materials. Many methods have been developed towards static or global control, however gaining simultaneously dynamic and local control over crystallization remains challenging. Here, we show spatiotemporal control over crystallization of retrograde (inverse) soluble compounds induced by locally heating water using near-infrared (NIR) laser light. We modulate the NIR light intensity to start, steer, and stop crystallization of calcium carbonate and laser-write with micrometer precision. Tailoring the crystallization conditions overcomes the inherently stochastic crystallization behavior and enables positioning single crystals of vaterite, calcite, and aragonite. We demonstrate straightforward extension of these principles toward other biorelevant compounds by patterning barium-, strontium-, and calcium carbonate, as well as strontium sulfate and calcium phosphate. Since many important compounds exhibit retrograde solubility behavior, NIR-induced heating may enable light-controlled crystallization with precise spatiotemporal control.
Aritra Biswas, Nir Lemcoff, Ofir Shelonchik, Doron Yesodi, Elad Yehezkel, Ella Yonit Finestone, Alexander Upcher, Yossi Weizmann
Photothermally heated colloidal synthesis of nanoparticles driven by silica-encapsulated plasmonic heat sources
In: Nature Communications, vol. 14, no. 6355, 2023, (Photothermal solution heating with nanoscale heat sources is an efficient alternative to conventional heating methods. Here, the authors use silica-encapsulated gold nanoparticles to drive the colloidal synthesis of iron oxide, silver, and palladium nanoparticles at lower temperatures.).
Using photons to drive chemical reactions has become an increasingly important field of chemistry. Plasmonic materials can provide a means to introduce the energy necessary for nucleation and growth of nanoparticles by efficiently converting visible and infrared light to heat. Moreover, the formation of crystalline nanoparticles has yet to be included in the extensive list of plasmonic photothermal processes. Herein, we establish a light-assisted colloidal synthesis of iron oxide, silver, and palladium nanoparticles by utilizing silica-encapsulated gold bipyramids as plasmonic heat sources. Our work shows that the silica surface chemistry and localized thermal hotspot generated by the plasmonic nanoparticles play crucial roles in the formation mechanism, enabling nucleation and growth at temperatures considerably lower than conventional heating. Additionally, the photothermal method is extended to anisotropic geometries and can be applied to obtain intricate assemblies inaccessible otherwise. This study enables photothermally heated nanoparticle synthesis in solution through the plasmonic effect and demonstrates the potential of this methodology.
S. Furkan Ozturk, Deb Kumar Bhowmick, Yael Kapon, Yutao Sang, Anil Kumar, Yossi Paltiel, Ron Naaman, Dimitar D. Sasselov
Chirality-induced avalanche magnetization of magnetite by an RNA precursor
In: Nature Communications, vol. 14, no. 6351, 2023, (Homochirality, a key feature of life, has unknown origins. Magnetic mineral surfaces can act as chiral agents, but are only weakly magnetized by nature. Here, the authors report the uniform magnetization of magnetite by an RNA precursor that spreads across the surface like an avalanche.).
Homochirality is a hallmark of life on Earth. To achieve and maintain homochirality within a prebiotic network, the presence of an environmental factor acting as a chiral agent and providing a persistent chiral bias to prebiotic chemistry is highly advantageous. Magnetized surfaces are prebiotically plausible chiral agents due to the chiral-induced spin selectivity (CISS) effect, and they were utilized to attain homochiral ribose-aminooxazoline (RAO), an RNA precursor. However, natural magnetic minerals are typically weakly magnetized, necessitating mechanisms to enhance their magnetization for their use as effective chiral agents. Here, we report the magnetization of magnetic surfaces by crystallizing enantiopure RAO, whereby chiral molecules induce a uniform surface magnetization due to the CISS effect, which spreads across the magnetic surface akin to an avalanche. Chirality-induced avalanche magnetization enables a feedback between chiral molecules and magnetic surfaces, which can amplify a weak magnetization and allow for highly efficient spin-selective processes on magnetic minerals.
Lu Zhang, Wencai Yi, Junfang Li, Guoying Wei, Guangcheng Xi, Lanqun Mao
Surfactant-free interfacial growth of graphdiyne hollow microspheres and the mechanistic origin of their SERS activity
In: Nature Communications, vol. 14, no. 6318, 2023, (The 2D carbon allotrope graphdiyne possesses a direct band gap, high charge carrier mobility, and uniformly distributed pores. Here, the authors report the surfactant-free growth of graphdiyne hollow microspheres and investigate the origin of their SERS activity.).
As a two-dimensional carbon allotrope, graphdiyne possesses a direct band gap, excellent charge carrier mobility, and uniformly distributed pores. Here, a surfactant-free growth method is developed to efficiently synthesize graphdiyne hollow microspheres at liquid‒liquid interfaces with a self-supporting structure, which avoids the influence of surfactants on product properties. We demonstrate that pristine graphdiyne hollow microspheres, without any additional functionalization, show a strong surface-enhanced Raman scattering effect with an enhancement factor of 3.7 × 10^7 and a detection limit of 1 × 10^−12 M for rhodamine 6 G, which is approximately 1000 times that of graphene. Experimental measurements and first-principles density functional theory simulations confirm the hypothesis that the surface-enhanced Raman scattering activity can be attributed to an efficiency interfacial charge transfer within the graphdiyne-molecule system.
Guomin Zhu, Benjamin A. Legg, Michel Sassi, Xinran Liang, Meirong Zong, Kevin M. Rosso, James J. De Yoreo
Crystal dissolution by particle detachment
In: Nature Communications, vol. 14, no. 6300, 2023, (Crystal dissolution has been predominately viewed as a process of ion-by-ion detachment into a surrounding solvent. Here, the authors report an alternative mechanism of dissolution by particle detachment.).
Crystal dissolution, which is a fundamental process in both natural and technological settings, has been predominately viewed as a process of ion-by-ion detachment into a surrounding solvent. Here we report a mechanism of dissolution by particle detachment (DPD) that dominates in mesocrystals formed via crystallization by particle attachment (CPA). Using liquid phase electron microscopy to directly observe dissolution of hematite crystals — both compact rhombohedra and mesocrystals of coaligned nanoparticles — we find that the mesocrystals evolve into branched structures, which disintegrate as individual sub-particles detach. The resulting dissolution rates far exceed those for equivalent masses of compact single crystals. Applying a numerical generalization of the Gibbs-Thomson effect, we show that the physical drivers of DPD are curvature and strain inherently tied to the original CPA process. Based on the generality of the model, we anticipate that DPD is widespread for both natural minerals and synthetic crystals formed via CPA.
Jeffrey R. Reimers, Tiexin Li, André P. Birvé, Likun Yang, Albert C. Aragonès, Thomas Fallon, Daniel S. Kosov, Nadim Darwish
Controlling piezoresistance in single molecules through the isomerisation of bullvalenes
In: Nature Communications, vol. 14, no. 6089 , 2023, (The quest for miniaturization of electromechanical nanosystems requires the use of single molecules as active components. Here, the authors develop a piezoresistor based on a single bullvalene molecule that changes its shape by a Cope rearrangement. ).
Nanoscale electro-mechanical systems (NEMS) displaying piezoresistance offer unique measurement opportunities at the sub-cellular level, in detectors and sensors, and in emerging generations of integrated electronic devices. Here, we show a single-molecule NEMS piezoresistor that operates utilising constitutional and conformational isomerisation of individual diaryl-bullvalene molecules and can be switched at 850 Hz. Observations are made using scanning tunnelling microscopy break junction (STMBJ) techniques to characterise piezoresistance, combined with blinking (current-time) experiments that follow single-molecule reactions in real time. A kinetic Monte Carlo methodology (KMC) is developed to simulate isomerisation on the experimental timescale, parameterised using density-functional theory (DFT) combined with non-equilibrium Green’s function (NEGF) calculations. Results indicate that piezoresistance is controlled by both constitutional and conformational isomerisation, occurring at rates that are either fast (equilibrium) or slow (non-equilibrium) compared to the experimental timescale. Two different types of STMBJ traces are observed, one typical of traditional experiments that are interpreted in terms of intramolecular isomerisation occurring on stable tipped-shaped metal-contact junctions, and another attributed to arise from junction‒interface restructuring induced by bullvalene isomerisation.
Zhenzhong Yang, Le Wang, Jeffrey A. Dhas, Mark H. Engelhard, Mark E. Bowden, Wen Liu, Zihua Zhu, Chongmin Wang, Scott A. Chambers, Peter V. Sushko, Yingge Du
Guided anisotropic oxygen transport in vacancy ordered oxides
In: Nature Communications, vol. 14, no. 6068, 2023, (Control of ion diffusion is instrumental in understanding the behavior and structural transformations of transition metal oxides. Here, the authors use in-situ TEM to reveal the atomic-scale evolution of the topotactic phase transition in BM-SFO triggered by the migration of oxygen ions under an external stimulus.).
Anisotropic and efficient transport of ions under external stimuli governs the operation and failure mechanisms of energy-conversion systems and microelectronics devices. However, fundamental understanding of ion hopping processes is impeded by the lack of atomically precise materials and probes that allow for the monitoring and control at the appropriate time- and length- scales. In this work, using in-situ transmission electron microscopy, we directly show that oxygen ion migration in vacancy ordered, semiconducting SrFeO2.5 epitaxial thin films can be guided to proceed through two distinctly different diffusion pathways, each resulting in different polymorphs of SrFeO2.75 with different ground electronic properties before reaching a fully oxidized, metallic SrFeO3 phase. The diffusion steps and reaction intermediates are revealed by means of ab-initio calculations. The principles of controlling oxygen diffusion pathways and reaction intermediates demonstrated here may advance the rational design of structurally ordered oxides for tailored applications and provide insights for developing devices with multiple states of regulation.
Chao Li, Christoph Kaspar, Ping Zhou, Jung-Ching Liu, Outhmane Chahib, Thilo Glatzel, Robert Häner, Ulrich Aschauer, Silvio Decurtins, Shi-Xia Liu, Michael Thoss, Ernst Meyer, Rémy Pawlak
Strong signature of electron-vibration coupling in molecules on Ag(111) triggered by tip-gated discharging
In: Nature Communications, vol. 14, no. 5956, 2023, (Electron-vibration coupling is driving advances in molecular electronics, spintronics, and quantum technology. Here, the authors succeeded in directly controlling vibronic excitations in tetrabromotetraazapyrene (TBTAP) molecules on the surface of Ag(111).).
Electron-vibration coupling is of critical importance for the development of molecular electronics, spintronics, and quantum technologies, as it affects transport properties and spin dynamics. The control over charge-state transitions and subsequent molecular vibrations using scanning tunneling microscopy typically requires the use of a decoupling layer. Here we show the vibronic excitations of tetrabromotetraazapyrene (TBTAP) molecules directly adsorbed on Ag(111) into an orientational glassy phase. The electron-deficient TBTAP is singly-occupied by an electron donated from the substrate, resulting in a spin 1/2 state, which is confirmed by a Kondo resonance. The TBTAP•− discharge is controlled by tip-gating and leads to a series of peaks in scanning tunneling spectroscopy. These occurrences are explained by combining a double-barrier tunneling junction with a Franck-Condon model including molecular vibrational modes. This work demonstrates that suitable precursor design enables gate-dependent vibrational excitations of molecules on a metal, thereby providing a method to investigate electron-vibration coupling in molecular assemblies without a decoupling layer.
Pengcheng Chen, Qiuhao Xu, Zijing Ding, Qing Chen, Jiyu Xu, Zhihai Cheng, Xiaohui Qiu, Bingkai Yuan, Sheng Meng, Nan Yao
Identification of a common ice nucleus on hydrophilic and hydrophobic close-packed metal surfaces
In: Nature Communications, vol. 14, no. 5813, 2023, (One key challenge in water science is to create a universal model that can predict the arrangement of water/solid interfaces. Here, the authors use STM and noncontact-AFM to discover common water clusters during the initial growth on hydrophilic and hydrophobic close-packed metal surfaces.).
Establishing a general model of heterogeneous ice nucleation has long been challenging because of the surface water structures found on different substrates. Identifying common water clusters, regardless of the underlying substrate, is one of the key steps toward solving this problem. Here, we demonstrate the presence of a common water cluster found on both hydrophilic Pt(111) and hydrophobic Cu(111) surfaces using scanning tunneling microscopy and non-contact atomic force microscopy. Water molecules self-assemble into a structure with a central flat-lying hexagon and three fused pentagonal rings, forming a cluster consisting of 15 individual water molecules. This cluster serves as a critical nucleus during ice nucleation on both surfaces: ice growth beyond this cluster bifurcates to form two-dimensional (three-dimensional) layers on hydrophilic (hydrophobic) surfaces. Our results reveal the inherent similarity and distinction at the initial stage of ice growth on hydrophilic and hydrophobic close-packed metal surfaces; thus, these observations provide initial evidence toward a general model for water-substrate interaction.
Yingying Zou, Chao Liu, Chaoqi Zhang, Ling Yuan, Jiaxin Li, Tong Bao, Guangfeng Wei, Jin Zou, Chengzhong Yu
Epitaxial growth of metal-organic framework nanosheets into single-crystalline orthogonal arrays
In: Nature Communications, vol. 14, no. 5780, 2023, (Constructing regular 3D superstructures from 2D nanosheets is a challenge. Here, the authors report the epitaxial growth of MOF nanosheets into single-crystalline orthogonal arrays with enhanced functional properties.).
Construction of two-dimensional nanosheets into three-dimensional regular structures facilitates the mass transfer and exploits the maximum potential of two-dimensional building blocks in applications such as catalysis. Here, we report the synthesis of metal-organic frameworks with an orthogonal nanosheet array. The assembly involves the epitaxial growth of single crystalline metal-organic framework nanosheets with a naturally non-preferred facet exposure as the shell on a cubic metal-organic framework as the core. The nanosheets, despite of two typical shapes and crystallographic orientations, also form a single crystalline orthogonally arrayed framework. The density and size of nanosheets in the core-shell-structured composite metal-organic frameworks can be well adjusted. Moreover, metal-organic frameworks with a single composition and hollow orthogonal nanosheet array morphology can be obtained. Benefiting from the unusual facet exposure and macroporous structure, the designed structure exhibits improved electrocatalytic oxygen evolution activity compared to conventional nanosheets.
Katharina Kaiser, Leonard-Alexander Lieske, Jascha Repp, Leo Gross
Charge-state lifetimes of single molecules on few monolayers of NaCl
In: Nature Communications, vol. 14, no. 4988, 2023, (Resonant charge transport to and from molecules and their corresponding charge-state transitions are critical to understanding electrically driven processes. Here, the authors investigate the charge-state lifetimes of single molecules through NaCl films of 3 to 5 monolayers thickness.).
In molecular tunnel junctions, where the molecule is decoupled from the electrodes by few-monolayers-thin insulating layers, resonant charge transport takes place by sequential charge transfer to and from the molecule which implies transient charging of the molecule. The corresponding charge state transitions, which involve tunneling through the insulating decoupling layers, are crucial for understanding electrically driven processes such as electroluminescence or photocurrent generation in such a geometry. Here, we use scanning tunneling microscopy to investigate the decharging of single ZnPc and H2Pc molecules through NaCl films of 3 to 5 monolayers thickness on Cu(111) and Au(111). To this end, we approach the tip to the molecule at resonant tunnel conditions up to a regime where charge transport is limited by tunneling through the NaCl film. The resulting saturation of the tunnel current is a direct measure of the lifetimes of the anionic and cationic states, i.e., the molecule’s charge-state lifetime, and thus provides a means to study charge dynamics and, thereby, exciton dynamics. Comparison of anion and cation lifetimes on different substrates reveals the critical role of the level alignment with the insulator’s conduction and valence band, and the metal-insulator interface state.
Daniel Medina-Lopez, Thomas Liu, Silvio Osella, Hugo Levy-Falk, Nicolas Rolland, Christine Elias, Gaspard Huber, Pranav Ticku, Loïc Rondin, Bruno Jousselme, David Beljonne, Jean-Sébastien Lauret, Stephane Campidelli
Interplay of structure and photophysics of individualized rod-shaped graphene quantum dots with up to 132 sp² carbon atoms
In: Nature Communications, vol. 14, no. 4728, 2023, (The use and characterization of graphene quantum dots is limited by their pronounced tendency to form aggregates. Here, the authors synthesize rod-shaped motifs of nanographenes with up to 132 sp² carbon atoms that are fully individualized, which allows the precise description of their intrinsic photophysical properties.).
Nanographene materials are promising building blocks for the growing field of low-dimensional materials for optics, electronics and biophotonics applications. In particular, bottom-up synthesized 0D graphene quantum dots show great potential as single quantum emitters. To fully exploit their exciting properties, the graphene quantum dots must be of high purity; the key parameter for efficient purification being the solubility of the starting materials. Here, we report the synthesis of a family of highly soluble and easily processable rod-shaped graphene quantum dots with fluorescence quantum yields up to 94%. This is uncommon for a red emission. The high solubility is directly related to the design of the structure, allowing for an accurate description of the photophysical properties of the graphene quantum dots both in solution and at the single molecule level. These photophysical properties were fully predicted by quantum-chemical calculations.
Yunjun Cao, Joel Mieres-Perez, Julien Frederic Rowen, Elsa Sanchez-Garcia, Wolfram Sander, Karina Morgenstern
Chirality control of a single carbene molecule by tip-induced van der Waals interactions
In: Nature Communications, vol. 14, no. 4500, 2023, (The control of molecular chirality is of great interest in stereochemistry and biochemistry. Here, the authors show how to alter the chirality dynamics of a single molecule through tip-induced van der Waals interactions.).
Non-covalent interactions such as van der Waals interactions and hydrogen bonds are crucial for the chiral induction and control of molecules, but it remains difficult to study them at the single-molecule level. Here, we report a carbene molecule on a copper surface as a prototype of an anchored molecule with a facile chirality change. We examine the influence of the attractive van der Waals interactions on the chirality change by regulating the tip-molecule distance, resulting in an excess of a carbene enantiomer. Our model study provides insight into the change of molecular chirality controlled by van der Waals interactions, which is fundamental for understanding the mechanisms of chiral induction and amplification.
Liang Qiao, Nia Pollard, Ravithree D. Senanayake, Zhi Yang, Minjung Kim, Arzeena S. Ali, Minh Tam Hoang, Nan Yao, Yimo Han, Rigoberto Hernandez, Andre Z. Clayborne, Matthew R. Jones
Atomically precise nanoclusters predominantly seed gold nanoparticle syntheses
In: Nature Communications, vol. 14, no. 4408, 2023, (In seed-mediated synthesis, small particulate precursors are added to a growth solution to initiate heterogeneous nucleation, allowing access to well-defined colloidal nanostructures. Here, the authors identify that one of the most commonly studied seed solutions is populated by atomically precise gold nanoclusters with 32 atoms.).
Seed-mediated synthesis strategies, in which small gold nanoparticle precursors are added to a growth solution to initiate heterogeneous nucleation, are among the most prevalent, simple, and productive methodologies for generating well-defined colloidal anisotropic nanostructures. However, the size, structure, and chemical properties of the seeds remain poorly understood, which partially explains the lack of mechanistic understanding of many particle growth reactions. Here, we identify the majority component in the seed solution as an atomically precise gold nanocluster, consisting of a 32-atom Au core with 8 halide ligands and 12 neutral ligands constituting a bound ion pair between a halide and the cationic surfactant: Au32X8[AQA+•X-]12 (X = Cl, Br; AQA = alkyl quaternary ammonium). Ligand exchange is dynamic and versatile, occurring on the order of minutes and allowing for the formation of 48 distinct Au32 clusters with AQAX (alkyl quaternary ammonium halide) ligands. Anisotropic nanoparticle syntheses seeded with solutions enriched in Au32X8[AQA+•X-]12 show narrower size distributions and fewer impurity particle shapes, indicating the importance of this cluster as a precursor to the growth of well-defined nanostructures.
Maximilian Sacherer, Frank Hampel, Henry Dube
Diaryl-hemiindigos as visible light, pH, and heat responsive four-state switches and application in photochromic transparent polymers
In: Nature Communications, vol. 14, no. 4382, 2023, (Hemiindigo derivatives can act as photoswitches, but their applicability is limited by synthetic challenges. Here, the authors report the synthesis of modified photoswitches and demonstrate four-state switching, chemical fueling, and reversible inscription into transparent polymers.).
Photoswitches are indispensable tools for responsive chemical nanosystems and are used today in almost all areas of the natural sciences. Hemiindigo (HI) derivatives have recently been introduced as potent photoswitches, but their full applicability has been hampered by the limited possibilities of their functionalization and structural modification. Here we report on a short and easy to diversify synthesis yielding diaryl-HIs bearing one additional aromatic residue at the central double bond. The resulting chromophores offer an advantageous property profile combining red-light responsiveness, high thermal bistability, strong isomer accumulations in both switching directions, strong photochromism, tunable acid responsiveness, and acid gating. With this progress, a broader structural realm becomes accessible for HI photoswitches, which can now be synthetically tailored for advanced future applications, e.g., in research on molecular machines and switches, in studies of photoisomerization mechanisms, or in the generation of smart and addressable materials. To showcase the potential of these distinct light-responsive molecular tools, we demonstrate four-state switching, chemical fueling, and reversible inscription into transparent polymers using green and red light as well as acid/base stimuli, in addition to a comprehensive photochemical study of all compounds.
Alexander Hensley, Thomas E. Videbæk, Hunter Seyforth, William M. Jacobs, W. Benjamin Rogers
Macroscopic photonic single crystals via seeded growth of DNA-coated colloids
In: Nature Communications, vol. 14, no. 4237, 2023, (DNA-programmed colloidal assembly of macroscopic crystals for photonic applications remains elusive. Here, the authors use insights from studies of nucleation and seeded growth to develop a two-step method for assembling macroscopic photonic crystals.).
Photonic crystals—a class of materials whose optical properties derive from their structure in addition to their composition—can be created by self-assembling particles whose sizes are comparable to the wavelengths of visible light. Proof-of-principle studies have shown that DNA can be used to guide the self-assembly of micrometer-sized colloidal particles into fully programmable crystal structures with photonic properties in the visible spectrum. However, the extremely temperature-sensitive kinetics of micrometer-sized DNA-functionalized particles has frustrated attempts to grow large, monodisperse crystals that are required for photonic metamaterial applications. Here we describe a robust two-step protocol for self-assembling single-domain crystals that contain millions of optical-scale DNA-functionalized particles: Monodisperse crystals are initially assembled in monodisperse droplets made by microfluidics, after which they are grown to macroscopic dimensions via seeded diffusion-limited growth. We demonstrate the generality of our approach by assembling different macroscopic single-domain photonic crystals with metamaterial properties, like structural coloration, that depend on the underlying crystal structure. By circumventing the fundamental kinetic traps intrinsic to crystallization of optical-scale DNA-coated colloids, we eliminate a key barrier to engineering photonic devices from DNA-programmed materials
Gang Wu, Chen Qian, Wen-Li Lv, Xiaona Zhao, Xian-Wei Liu
Dynamic imaging of interfacial electrochemistry on single Ag nanowires by azimuth-modulated plasmonic scattering interferometry
In: Nature Communications, vol. 14, no. 4194, 2023, (Direct visualization of the chemical dynamics of surfaces in solution is essential to gain mechanistic insights into nanocatalysis and electrochemistry. Here, the authors demonstrate the imaging of dynamic interfacial changes on a single nanowire during chemical reactions using azimuthally modulated plasmonic scattering interferometry.).
Direct visualization of surface chemical dynamics in solution is essential for understanding the mechanisms involved in nanocatalysis and electrochemistry; however, it is challenging to achieve high spatial and temporal resolution. Here, we present an azimuth-modulated plasmonic imaging technique capable of imaging dynamic interfacial changes. The method avoids strong interference from reflected light and consequently eliminates the parabolic-like interferometric patterns in the images, allowing for a 67-fold increase in the spatial resolution of plasmonic imaging. We demonstrate that this optical imaging approach enables comprehensive analyses of surface chemical dynamics and identification of previously unknown surface reaction heterogeneity by investigating electrochemical redox reactions over single silver nanowires as an example. This work provides a general strategy for high-resolution plasmonic imaging of surface electrochemical dynamics and other interfacial chemical reactions, complementing existing surface characterization methods.
Yunqing Kang, Ovidiu Cretu, Jun Kikkawa, Koji Kimoto, Hiroki Nara, Asep Sugih Nugraha, Hiroki Kawamoto, Miharu Eguchi, Ting Liao, Ziqi Sun, Toru Asahi, Yusuke Yamauchi
Mesoporous multimetallic nanospheres with exposed highly entropic alloy sites
In: Nature Communications, vol. 14, no. 4182, 2023, (Nanostructured materials made from multimetal alloys are attractive for catalytic applications. Here, the authors propose a soft-templating approach to prepare mesoporous PtPdRhRuCu nanospheres that feature exposed porous structures rich in highly entropic alloy sites.).
Multimetallic alloys (MMAs) with various compositions enrich the materials library with increasing diversity and have received much attention in catalysis applications. However, precisely shaping MMAs in mesoporous nanostructures and mapping the distributions of multiple elements remain big challenge due to the different reduction kinetics of various metal precursors and the complexity of crystal growth. Here we design a one-pot wet-chemical reduction approach to synthesize core–shell motif PtPdRhRuCu mesoporous nanospheres (PtPdRhRuCu MMNs) using a diblock copolymer as the soft template. The PtPdRhRuCu MMNs feature adjustable compositions and exposed porous structures rich in highly entropic alloy sites. The formation processes of the mesoporous structures and the reduction and growth kinetics of different metal precursors of PtPdRhRuCu MMNs are revealed. The PtPdRhRuCu MMNs exhibit robust electrocatalytic hydrogen evolution reaction (HER) activities and low overpotentials of 10, 13, and 28 mV at a current density of 10 mA cm−2 in alkaline (1.0 M KOH), acidic (0.5 M H2SO4), and neutral (1.0 M phosphate buffer solution (PBS)) electrolytes, respectively. The accelerated kinetics of the HER in PtPdRhRuCu MMNs are derived from multiple compositions with synergistic interactions among various metal sites and mesoporous structures with excellent mass/electron transportation characteristics.
Thermometry on individual nanoparticles highlights the impact of bimetallic interfaces
In: Nature Communications, vol. 14, no. 3812, 2023, (A new study sheds light on the impact of bimetallic interfaces in nanomaterials for heat generation using single-particle thermometry. Moving from nanoparticle ensembles to single particles is key to developing consistent knowledge of material performance and nanoscale processes, but also involves assumptions and definitions that require careful consideration.).
A new study sheds light on the impact of bimetallic interfaces in nanomaterials for heat generation using single-particle thermometry. Moving from nanoparticle ensembles to single particles is key to developing consistent knowledge of material performance and nanoscale processes, but also involves assumptions and definitions that require careful consideration.
Julian Gargiulo, Matias Herran, Ianina L. Violi, Ana Sousa-Castillo, Luciana P. Martinez, Simone Ezendam, Mariano Barella, Helene Giesler, Roland Grzeschik, Sebastian Schlücker, Stefan A. Maier, Fernando D. Stefani, Emiliano Cortés
Impact of bimetallic interface design on heat generation in plasmonic Au/Pd nanostructures studied by single-particle thermometry
In: Nature Communications, vol. 14, no. 3813, 2023, (The conversion of light into heat is a key process for plasmonic-catalytic applications. Here, the authors investigate how the design of the bimetallic interface affects the photothermal heating properties in Au/Pd nanostructures by applying thermometry at the single-particle level.).
Localized surface plasmons are lossy and generate heat. However, accurate measurement of the temperature of metallic nanoparticles under illumination remains an open challenge, creating difficulties in the interpretation of results across plasmonic applications. Particularly, there is a quest for understanding the role of temperature in plasmon-assisted catalysis. Bimetallic nanoparticles combining plasmonic with catalytic metals are raising increasing interest in artificial photosynthesis and the production of solar fuels. Here, we perform single-particle thermometry measurements to investigate the link between morphology and light-to-heat conversion of colloidal Au/Pd nanoparticles with two different configurations: core–shell and core-satellite. It is observed that the inclusion of Pd as a shell strongly reduces the photothermal response in comparison to the bare cores, while the inclusion of Pd as satellites keeps photothermal properties almost unaffected. These results contribute to a better understanding of energy conversion processes in plasmon-assisted catalysis.
Jiapeng Zheng, Christina Boukouvala, George R. Lewis, Yicong Ma, Yang Chen, Emilie Ringe, Lei Shao, Zhifeng Huang, Jianfang Wang
Halide-assisted differential growth of chiral nanoparticles with threefold rotational symmetry
In: Nature Communications, vol. 14, no. 3783, 2023, (Expanding the library of chiral plasmonic nanoparticles will foster the development of chiroptical applications. Here, the authors apply halide-assisted differential growth to convert Au nanodisks into triskelion-shaped chiral nanoparticles with threefold rotational symmetry.).
Enriching the library of chiral plasmonic nanoparticles that can be chemically mass-produced will greatly facilitate the applications of chiral plasmonics in areas ranging from constructing optical metamaterials to sensing chiral molecules and activating immune cells. Here we report on a halide-assisted differential growth strategy that can direct the anisotropic growth of chiral Au nanoparticles with tunable sizes and diverse morphologies. Anisotropic Au nanodisks are employed as seeds to yield triskelion-shaped chiral nanoparticles with threefold rotational symmetry and high dissymmetry factors. The averaged scattering g-factors of the L- and D-nanotriskelions are as large as 0.57 and − 0.49 at 650 nm, respectively. The Au nanotriskelions have been applied in chiral optical switching devices and chiral nanoemitters. We also demonstrate that the manipulation of the directional growth rate enables the generation of a variety of chiral morphologies in the presence of homochiral ligands.
Kunmo Koo, Bo Shen, Sung-Il Baik, Zugang Mao, Paul J. M. Smeets, Ivan Cheuk, Kun He, Roberto dos Reis, Liliang Huang, Zihao Ye, Xiaobing Hu, Chad A. Mirkin, Vinayak P. Dravid
Formation mechanism of high-index faceted Pt-Bi alloy nanoparticles by evaporation-induced growth from metal salts
In: Nature Communications, vol. 14, no. 3790, 2023, (Faceted nanoparticles with high-index planes exposed usually bear promising material functionalities. Here, the authors directly observe the coarsening and facet regulation process of tetrahexahedra Pt nanoparticles by using in-situ gas-phase TEM.).
Nanoparticles with high-index facets are intriguing because such facets can lend the structure useful functionality, including enhanced catalytic performance and wide-ranging optical tunability. Ligand-free solid-state syntheses of high index-facet nanoparticles, through an alloying-dealloying process with foreign volatile metals, are attractive owing to their materials generality and high yields. However, the role of foreign atoms in stabilizing the high-index facets and the dynamic nature of the transformation including the coarsening and facet regulation process are still poorly understood. Herein, the transformation of Pt salts to spherical seeds and then to tetrahexahedra, is studied in situ via gas-cell transmission electron microscopy. The dynamic behaviors of the alloying and dealloying process, which involves the coarsening of nanoparticles and consequent facet regulation stage are captured in the real time with a nanoscale spatial resolution. Based on additional direct evidence obtained using atom probe tomography and density functional theory calculations, the underlying mechanisms of the alloying-dealloying process are uncovered, which will facilitate broader explorations of high-index facet nanoparticle synthesis.
Hak June Lee, Seongbin Im, Dongju Jung, Kyuri Kim, Jong Ah Chae, Jaemin Lim, Jeong Woo Park, Doyoon Shin, Kookheon Char, Byeong Guk Jeong, Ji-Sang Park, Euyheon Hwang, Doh C. Lee, Young-Shin Park, Hyung-Jun Song, Jun Hyuk Chang, Wan Ki Bae
Coherent heteroepitaxial growth of I-III-VI2 Ag(In,Ga)S2 colloidal nanocrystals with near-unity quantum yield for use in luminescent solar concentrators
In: Nature Communications, vol. 14, no. 3779, 2023, (Colloidal semiconductor core-shell nanocrystals are sought after for photonic applications. Here, the authors report coherent heteroepitaxial growth of Ag(In,Ga)S2 core-shell nanocrystals with near-unity photoluminescence quantum yield across almost the full visible range.).
Colloidal Ag(In,Ga)S2 nanocrystals (AIGS NCs) with the band gap tunability by their size and composition within visible range have garnered surging interest. High absorption cross-section and narrow emission linewidth of AIGS NCs make them ideally suited to address the challenges of Cd-free NCs in wide-ranging photonic applications. However, AIGS NCs have shown relatively underwhelming photoluminescence quantum yield (PL QY) to date, primarily because coherent heteroepitaxy has not been realized. Here, we report the heteroepitaxy for AIGS-AgGaS2 (AIGS-AGS) core-shell NCs bearing near-unity PL QYs in almost full visible range (460 to 620 nm) and enhanced photochemical stability. Key to the successful growth of AIGS-AGS NCs is the use of the Ag-S-Ga(OA)2 complex, which complements the reactivities among cations for both homogeneous AIGS cores in various compositions and uniform AGS shell growth. The heteroepitaxy between AIGS and AGS results in the Type I heterojunction that effectively confines charge carriers within the emissive core without optically active interfacial defects. AIGS-AGS NCs show higher extinction coefficient and narrower spectral linewidth compared to state-of-the-art heavy metal-free NCs, prompting their immediate use in practicable applications including displays and luminescent solar concentrators (LSCs).
Chang Liu, Yan Zhao, Tai-Song Zhang, Cheng-Bo Tao, Wenwen Fei, Sheng Zhang, Man-Bo Li
Asymmetric transformation of achiral gold nanoclusters with negative nonlinear dependence between chiroptical activity and enantiomeric excess
In: Nature Communications, vol. 14, no. 3730, 2023, (Atomically precise metal nanoclusters provide an ideal platform for studying chirality at the nanoscale. Here, the authors use a phosphoramidite ligand as a chiral inducer to asymmetrically transform achiral into chiral gold nanoclusters with negative nonlinear CD-ee dependence.).
The investigation of chirality at the nanoscale is important to bridge the gap between molecular and macroscopic chirality. Atomically precise metal nanoclusters provide an ideal platform for this research, while their enantiopure preparation poses a challenge. Here, we describe an efficient approach to enantiopure metal nanoclusters via asymmetric transformation, that is, achiral Au23(SC6H11)16 nanoclusters are converted into chiral and enantiopure Au24(L)2(SC6H11)16 nanoclusters by a chiral inducer phosphoramidite (L). Two enantiomers of Au24(L)2(SC6H11)16 are obtained and the crystal structures reveal their hierarchical chirality, which originates from the two introduced chiral L molecules, the transformation-triggered asymmetric rearrangement of the staple motifs on the surface of the gold core, and the helical arrangement of nanocluster molecules. The construction of this type of enantiomerically pure nanoclusters is achieved based on the easy-to-synthesize and modular L. Lastly, the chirality-related chiroptical performance was investigated, revealing a negative nonlinear CD-ee dependence.
Nathaniel H. Park, Matteo Manica, Jannis Born, James L. Hedrick, Tim Erdmann, Dmitry Yu. Zubarev, Nil Adell-Mill, Pedro L. Arrechea
Artificial intelligence driven design of catalysts and materials for ring opening polymerization using a domain-specific language
In: Nature Communications, vol. 14, no. 3686, 2023, (Developing accessible polymeric materials is a challenging task for generative AI models. Here, the authors show that a domain-specific language enables the use of historical data to tune generative models to produce experimentally achievable material designs.).
Advances in machine learning (ML) and automated experimentation are poised to vastly accelerate research in polymer science. Data representation is a critical aspect for enabling ML integration in research workflows, yet many data models impose significant rigidity making it difficult to accommodate a broad array of experiment and data types found in polymer science. This inflexibility presents a significant barrier for researchers to leverage their historical data in ML development. Here we show that a domain specific language, termed Chemical Markdown Language (CMDL), provides flexible, extensible, and consistent representation of disparate experiment types and polymer structures. CMDL enables seamless use of historical experimental data to fine-tune regression transformer (RT) models for generative molecular design tasks. We demonstrate the utility of this approach through the generation and the experimental validation of catalysts and polymers in the context of ring-opening polymerization—although we provide examples of how CMDL can be more broadly applied to other polymer classes. Critically, we show how the CMDL tuned model preserves key functional groups within the polymer structure, allowing for experimental validation. These results reveal the versatility of CMDL and how it facilitates translation of historical data into meaningful predictive and generative models to produce experimentally actionable output.
Chun Tang, Thijs Stuyver, Taige Lu, Junyang Liu, Yiling Ye, Tengyang Gao, Luchun Lin, Jueting Zheng, Wenqing Liu, Jia Shi, Sason Shaik, Haiping Xia, Wenjing Hong
Voltage-driven control of single-molecule keto-enol equilibrium in a two-terminal junction system
In: Nature Communications, vol. 14, no. 3657, 2023, (Keto-enol tautomerism offers a promising platform for modulating charge transport at the nanoscale. Here, the authors show that the keto-enol equilibrium can be modulated on the single-molecule scale by controlling charge injection in a two-terminal junction system.).
Keto-enol tautomerism, describing an equilibrium involving two tautomers with distinctive structures, provides a promising platform for modulating nanoscale charge transport. However, such equilibria are generally dominated by the keto form, while a high isomerization barrier limits the transformation to the enol form, suggesting a considerable challenge to control the tautomerism. Here, we achieve single-molecule control of a keto-enol equilibrium at room temperature by using a strategy that combines redox control and electric field modulation. Based on the control of charge injection in the single-molecule junction, we could access charged potential energy surfaces with opposite thermodynamic driving forces, i.e., exhibiting a preference for the conducting enol form, while the isomerization barrier is also significantly reduced. Thus, we could selectively obtain desired and stable tautomers, which leads to significant modulation of the single-molecule conductance. This work highlights the concept of single-molecule control of chemical reactions on more than one potential energy surface.
Xuesong Yang, Linfeng Lan, Liang Li, Jinyang Yu, Xiaokong Liu, Ying Tao, Quan-Hong Yang, Panče Naumov, Hongyu Zhang
Collective photothermal bending of flexible organic crystals modified with MXene-polymer multilayers as optical waveguide arrays
In: Nature Communications, vol. 14, no. 3627, 2023, (Organic crystals represent potential alternatives to silicon dioxide due to their high flexibility and controllable properties. Here, the authors prepared a hybrid organic crystal material that responds mechanically to infrared light.).
The performance of any engineering material is naturally limited by its structure, and while each material suffers from one or multiple shortcomings when considered for a particular application, these can be potentially circumvented by hybridization with other materials. By combining organic crystals with MXenes as thermal absorbers and charged polymers as adhesive counter-ionic components, we propose a simple access to flexible hybrid organic crystal materials that have the ability to mechanically respond to infrared light. The ensuing hybrid organic crystals are durable, respond fast, and can be cycled between straight and deformed state repeatedly without fatigue. The point of flexure and the curvature of the crystals can be precisely controlled by modulating the position, duration, and power of thermal excitation, and this control can be extended from individual hybrid crystals to motion of ordered two-dimensional arrays of such crystals. We also demonstrate that excitation can be achieved over very long distances (>3 m). The ability to control the shape with infrared light adds to the versatility in the anticipated applications of organic crystals, most immediately in their application as thermally controllable flexible optical waveguides for signal transmission in flexible organic electronics.
Sungwook Choi, Sang Won Im, Ji-Hyeok Huh, Sungwon Kim, Jaeseung Kim, Yae-Chan Lim, Ryeong Myeong Kim, Jeong Hyun Han, Hyeohn Kim, Michael Sprung, Su Yong Lee, Wonsuk Cha, Ross Harder, Seungwoo Lee, Ki Tae Nam, Hyunjung Kim
Strain and crystallographic identification of the helically concaved gap surfaces of chiral nanoparticles
In: Nature Communications, vol. 14, no. 3615 , 2023, (Identifying the 3D crystal plane and strain field distributions of nanocrystals with concave surfaces is challenging. Here, the authors analyze the hidden concave gaps of chiral nanoparticles by using coherent Bragg X-ray diffraction imaging.).
Identifying the three-dimensional (3D) crystal plane and strain-field distributions of nanocrystals is essential for optical, catalytic, and electronic applications. However, it remains a challenge to image concave surfaces of nanoparticles. Here, we develop a methodology for visualizing the 3D information of chiral gold nanoparticles ≈ 200 nm in size with concave gap structures by Bragg coherent X-ray diffraction imaging. The distribution of the high-Miller-index planes constituting the concave chiral gap is precisely determined. The highly strained region adjacent to the chiral gaps is resolved, which was correlated to the 432-symmetric morphology of the nanoparticles and its corresponding plasmonic properties are numerically predicted from the atomically defined structures. This approach can serve as a comprehensive characterization platform for visualizing the 3D crystallographic and strain distributions of nanoparticles with a few hundred nanometers, especially for applications where structural complexity and local heterogeneity are major determinants, as exemplified in plasmonics.
Si-Zhe Sheng, Jin-Long Wang, Bin Zhao, Zhen He, Xue-Fei Feng, Qi-Guo Shang, Cheng Chen, Gang Pei, Jun Zhou, Jian-Wei Liu, Shu-Hong Yu
Nanowire-based smart windows combining electro- and thermochromics for dynamic regulation of solar radiation
In: Nature Communications, vol. 14, no. 3231, 2023, (Smart windows offer more efficient sunlight modulation and heat management. Here, the authors propose a co-assembly strategy to produce smart windows that combine electrochromic and thermochromic functions with tunable components and ordered structures for dynamic solar radiation regulation.).
Smart window is an attractive option for efficient heat management to minimize energy consumption and improve indoor living comfort owing to their optical properties of adjusting sunlight. To effectively improve the sunlight modulation and heat management capability of smart windows, here, we propose a co-assembly strategy to fabricate the electrochromic and thermochromic smart windows with tunable components and ordered structures for the dynamic regulation of solar radiation. Firstly, to enhance both illumination and cooling efficiency in electrochromic windows, the aspect ratio and mixed type of Au nanorods are tuned to selectively absorb the near-infrared wavelength range of 760 to 1360 nm. Furthermore, when assembled with electrochromic W18O49 nanowires in the colored state, the Au nanorods exhibit a synergistic effect, resulting in a 90% reduction of near-infrared light and a corresponding 5 °C cooling effect under 1-sun irradiation. Secondly, to extend the fixed response temperature value to a wider range of 30–50 °C in thermochromic windows, the doping amount and mixed type of W-VO2 nanowires are carefully regulated. Last but not the least, the ordered assembly structure of the nanowires can greatly reduce the level of haze and enhance visibility in the windows.
Ji Soo Kim, Hogeun Chang, Sungsu Kang, Seungwoo Cha, Hanguk Cho, Seung Jae Kwak, Namjun Park, Younhwa Kim, Dohun Kang, Chyan Kyung Song, Jimin Kwag, Ji-Sook Hahn, Won Bo Lee, Taeghwan Hyeon, Jungwon Park
Critical roles of metal–ligand complexes in the controlled synthesis of various metal nanoclusters
In: Nature Communications, vol. 14, no. 3201, 2023, (Metal-thiolate complexes are the precursors to atomically precise metal nanoclusters. Here, the authors show that the extent of metal-ligand interaction is key to controlling the size and uniformity in the synthesis of metal nanoclusters.).
Metal nanoclusters (NCs), an important class of nanoparticles (NPs), are extremely small in size and possess quasi-molecular properties. Due to accurate stoichiometry of constituent atoms and ligands, NCs have strong structure-property relationship. The synthesis of NCs is seemingly similar to that of NPs as both are formed by colloidal phase transitions. However, they are considerably different because of metal-ligand complexes in NC synthesis. Reactive ligands can convert metal salts to complexes, actual precursors to metal NCs. During the complex formation, various metal species occur, having different reactivity and fraction depending on synthetic conditions. It can alter their degree of participation in NC synthesis and the homogeneity of final products. Herein, we investigate the effects of complex formation on the entire NC synthesis. By controlling the fraction of various Au species showing different reactivity, we find that the extent of complex formation alters reduction kinetics and the uniformity of Au NCs. We demonstrate that this concept can be universally applied to synthesize Ag, Pt, Pd, and Rh NCs.
Zezhou Li, Zhiheng Xie, Yao Zhang, Xilong Mu, Jisheng Xie, Hai-Jing Yin, Ya-Wen Zhang, Colin Ophus, Jihan Zhou
Probing the atomically diffuse interfaces in Pd@Pt core-shell nanoparticles in three dimensions
In: Nature Communications, vol. 14, no. 2934, 2023, (Deciphering the structure and composition of bimetallic nanomaterial interfaces is key to understanding their properties. Here, the authors investigate the diffuse interfaces in Pd@Pt core-shell nanoparticles in 3D using electron tomography with atomic resolution.).
Deciphering the three-dimensional atomic structure of solid-solid interfaces in core-shell nanomaterials is the key to understand their catalytical, optical and electronic properties. Here, we probe the three-dimensional atomic structures of palladium-platinum core-shell nanoparticles at the single-atom level using atomic resolution electron tomography. We quantify the rich structural variety of core-shell nanoparticles with heteroepitaxy in 3D at atomic resolution. Instead of forming an atomically-sharp boundary, the core-shell interface is found to be atomically diffuse with an average thickness of 4.2 Å, irrespective of the particle’s morphology or crystallographic texture. The high concentration of Pd in the diffusive interface is highly related to the free Pd atoms dissolved from the Pd seeds, which is confirmed by atomic images of Pd and Pt single atoms and sub-nanometer clusters using cryogenic electron microscopy. These results advance our understanding of core-shell structures at the fundamental level, providing potential strategies into precise nanomaterial manipulation and chemical property regulation.
Masahiro Hayakawa, Naoyuki Sunayama, Shu I. Takagi, Yu Matsuo, Asuka Tamaki, Shigehiro Yamaguchi, Shu Seki, Aiko Fukazawa
Flattened 1D fragments of fullerene C60 that exhibit robustness toward multi-electron reduction
In: Nature Communications, vol. 14, no. 2741, 2023, (Fullerenes are compelling molecular materials, but the reason for their high robustness to multi-electron reduction is still debated. Here, the authors synthesize flattened 1D fragments of fullerene C₆₀ with high robustness against multi-electron reduction.).
Fullerenes are compelling molecular materials owing to their exceptional robustness toward multi-electron reduction. Although scientists have attempted to address this feature by synthesizing various fragment molecules, the origin of this electron affinity remains unclear. Several structural factors have been suggested, including high symmetry, pyramidalized carbon atoms, and five-membered ring substructures. To elucidate the role of the five-membered ring substructures without the influence of high symmetry and pyramidalized carbon atoms, we herein report the synthesis and electron-accepting properties of oligo(biindenylidene)s, a flattened one-dimensional fragment of fullerene C60. Electrochemical studies corroborated that oligo(biindenylidene)s can accept electrons up to equal to the number of five-membered rings in their main chains. Moreover, ultraviolet/visible/near-infrared absorption spectroscopy revealed that oligo(biindenylidene)s exhibit enhanced absorption covering the entire visible region relative to C60. These results highlight the significance of the pentagonal substructure for attaining stability toward multi-electron reduction and provide a strategy for the molecular design of electron-accepting π-conjugated hydrocarbons even without electron-withdrawing groups.
Weichao Peng, Shuaihu Yan, Ke Zhou, Hai-Chen Wu, Lei Liu, Yuliang Zhao
High-resolution discrimination of homologous and isomeric proteinogenic amino acids in nanopore sensors with ultrashort single-walled carbon nanotubes
In: Nature Communications, vol. 14, no. 2662, 2023, (Ultrashort single-walled carbon nanotubes inserted in lipid bilayers can be used as nanopore sensors. Here, the authors demonstrate the high-resolution discrimination of homologous and isomeric proteinogenic amino acids with such carbon-based nanopores.).
The hollow and tubular structure of single-walled carbon nanotubes (SWCNTs) makes them ideal candidates for making nanopores. However, the heterogeneity of SWCNTs hinders the fabrication of robust and reproducible carbon-based nanopore sensors. Here we develop a modified density gradient ultracentrifugation approach to separate ultrashort (≈5-10 nm) SWCNTs with a narrow conductance range and construct high-resolution nanopore sensors with those tubes inserted in lipid bilayers. By conducting ionic current recordings and fluorescent imaging of Ca2+ flux through different nanopores, we prove that the ion mobilities in SWCNT nanopores are 3-5 times higher than the bulk mobility. Furthermore, we employ SWCNT nanopores to discriminate homologue or isomeric proteinogenic amino acids, which are challenging tasks for other nanopore sensors. These successes, coupled with the building of SWCNT nanopore arrays, may constitute a crucial part of the recently burgeoning protein sequencing technologies.
Li Zhai, Sara T. Gebre, Bo Chen, Dan Xu, Junze Chen, Zijian Li, Yawei Liu, Hua Yang, Chongyi Ling, Yiyao Ge, Wei Zhai, Changsheng Chen, Lu Ma, Qinghua Zhang, Xuefei Li, Yujie Yan, Xinyu Huang, Lujiang Li, Zhiqiang Guan, Chen-Lei Tao, Zhiqi Huang, Hongyi Wang, Jinze Liang, Ye Zhu, Chun-Sing Lee, Peng Wang, Chunfeng Zhang, Lin Gu, Yonghua Du, Tianquan Lian, Hua Zhang, Xue-Jun Wu
Epitaxial growth of highly symmetrical branched noble metal-semiconductor heterostructures with efficient plasmon-induced hot-electron transfer
In: Nature Communications, vol. 14, no. 2538, 2023, (Epitaxial growth of heterostructures composed of materials with large lattice mismatch is challenging. Here, the authors reported the epitaxy of II-VI semiconductor nanorods on plasmonic noble metal, despite a lattice mismatch of more than 40%.).
Epitaxial growth is one of the most commonly used strategies to precisely tailor heterostructures with well-defined compositions, morphologies, crystal phases, and interfaces for various applications. However, as epitaxial growth requires a small interfacial lattice mismatch between the components, it remains a challenge for the epitaxial synthesis of heterostructures constructed by materials with large lattice mismatch and/or different chemical bonding, especially the noble metal-semiconductor heterostructures. Here, we develop a noble metal-seeded epitaxial growth strategy to prepare highly symmetrical noble metal-semiconductor branched heterostructures with desired spatial configurations, i.e., twenty CdS (or CdSe) nanorods epitaxially grown on twenty exposed (111) facets of Ag icosahedral nanocrystal, albeit a large lattice mismatch (more than 40%). Importantly, a high quantum yield (QY) of plasmon-induced hot-electron transferred from Ag to CdS was observed in epitaxial Ag-CdS icosapods (18.1%). This work demonstrates that epitaxial growth can be achieved in heterostructures composed of materials with large lattice mismatches. The constructed epitaxial noble metal-semiconductor interfaces could be an ideal platform for investigating the role of interfaces in various physicochemical processes.
Li-Juan Liu, Fahri Alkan, Shengli Zhuang, Dongyi Liu, Tehseen Nawaz, Jun Guo, Xiaozhou Luo, Jian He
Atomically precise gold nanoclusters at the molecular-to-metallic transition with intrinsic chirality from surface layers
In: Nature Communications, vol. 14, no. 2397, 2023, (Chiral metal nanoclusters prepared from achiral ligands generally contain chiral kernel structures. Here, the authors report an alternative type of gold nanoclusters whose intrinsic chirality arises solely from the arrangement of the organic components on their surface.).
The advances in determining the total structure of atomically precise metal nanoclusters have prompted extensive exploration into the origins of chirality in nanoscale systems. While chirality is generally transferrable from the surface layer to the metal–ligand interface and kernel, we present here an alternative type of gold nanoclusters (138 gold core atoms with 48 2,4-dimethylbenzenethiolate surface ligands) whose inner structures are not asymmetrically induced by chiral patterns of the outermost aromatic substituents. This phenomenon can be explained by the highly dynamic behaviors of aromatic rings in the thiolates assembled via π − π stacking and C − H···π interactions. In addition to being a thiolate-protected nanocluster with uncoordinated surface gold atoms, the reported Au138 motif expands the size range of gold nanoclusters having both molecular and metallic properties. Our current work introduces an important class of nanoclusters with intrinsic chirality from surface layers rather than inner structures and will aid in elucidating the transition of gold nanoclusters from their molecular to metallic states.
Huiru Liu, Heping Li, Yu He, Peng Cheng, Yi-Qi Zhang, Baojie Feng, Hui Li, Kehui Wu, Lan Chen
Condensation and asymmetric amplification of chirality in achiral molecules adsorbed on an achiral surface
In: Nature Communications, vol. 14, no. 2100, 2023, (The origin of homochirality in nature is an important but open question. Here, the authors provide insight into the physicochemical origin of homochirality through surface adsorption on the model of adlayers of achiral carbon monoxide molecules on an achiral Au(111) surface.).
The origin of homochirality in nature is an important but open question. Here, we demonstrate a simple organizational chiral system constructed by achiral carbon monoxide (CO) molecules adsorbed on an achiral Au(111) substrate. Combining scanning tunneling microscope (STM) measurements with density-functional-theory (DFT) calculations, two dissymmetric cluster phases consisting of chiral CO heptamers are revealed. By applied high bias voltage, the stable racemic cluster phase can be transformed into a metastable uniform phase consisting of CO monomers. Further, during the recondensation of a cluster phase after lowering down bias voltage, an enantiomeric excess and its chiral amplification occur, resulting in a homochirality. Such asymmetry amplification is found to be both kinetically feasible and thermodynamically favorable. Our observations provide insight into the physicochemical origin of homochirality through surface adsorption and suggest a general phenomenon that can influence enantioselective chemical processes such as chiral separations and heterogeneous asymmetric catalysis.
Nanoscale thermodynamics needs the concept of a disjoining chemical potential
In: Nature Communications, vol. 14, no. 1824, 2023, (Matter behaves differently at the nanoscale. Here, the author introduces the concept of a disjoining chemical potential for nanoscale thermodynamics, showing that thermodynamic functions depend on the environment, and suggests possible experimental verifications.).
Disjoining pressure was discovered by Derjaguin in 1930’s, which describes the difference between the pressure of a strongly confined fluid and the corresponding one in a bulk phase. It has been revealed recently that the disjoining pressure is at the origin of distinct differential and integral surface tensions for strongly confined fluids. Here we show how the twin concept, disjoining chemical potential, arises in a reminiscent way although it comes out eighty years later. This twin concept advances our understanding of nanoscale thermodynamics. Ensemble-dependence (or environment-dependence) is one hallmark of thermodynamics of small systems. We show that integral surface tension is ensemble-dependent while differential surface tension is not. Moreover, two generalized Gibbs-Duhem equations involving integral surface tensions are derived, as well as two additional adsorption equations relating surface tensions to adsorption-induced strains. All the results obtained in this work further evidence that an approach alternative of Hill’s nanothermodynamics is possible, by extending Gibbs surface thermodynamics instead of resorting to Hill’s replica trick. Moreover, we find a compression-expansion hysteresis without any underlying phase transition.
Eleonora Calì, Melonie P. Thomas, Rama Vasudevan, Ji Wu, Oriol Gavalda-Diaz, Katharina Marquardt, Eduardo Saiz, Dragos Neagu, Raymond R. Unocic, Stephen C. Parker, Beth S. Guiton, David J. Payne
Real-time insight into the multistage mechanism of nanoparticle exsolution from a perovskite host surface
In: Nature Communications, vol. 14, no. 1754, 2023, (The separation of nanoparticles from oxide hosts by exsolution forms the basis for catalytic and energy-related applications. Here, the authors elucidate the multistep mechanism of exsolution at perovskite surfaces by combining real-time electron microscopy and computational methods.).
In exsolution, nanoparticles form by emerging from oxide hosts by application of redox driving forces, leading to transformative advances in stability, activity, and efficiency over deposition techniques, and resulting in a wide range of new opportunities for catalytic, energy and net-zero-related technologies. However, the mechanism of exsolved nanoparticle nucleation and perovskite structural evolution, has, to date, remained unclear. Herein, we shed light on this elusive process by following in real time Ir nanoparticle emergence from a SrTiO3 host oxide lattice, using in situ high-resolution electron microscopy in combination with computational simulations and machine learning analytics. We show that nucleation occurs via atom clustering, in tandem with host evolution, revealing the participation of surface defects and host lattice restructuring in trapping Ir atoms to initiate nanoparticle formation and growth. These insights provide a theoretical platform and practical recommendations to further the development of highly functional and broadly applicable exsolvable materials.
Mo Xie, Weina Fang, Zhibei Qu, Yang Hu, Yichi Zhang, Jie Chao, Jiye Shi, Lihua Wang, Lianhui Wang, Yang Tian, Chunhai Fan, Huajie Liu
High-entropy alloy nanopatterns by prescribed metallization of DNA origami templates
In: Nature Communications, vol. 14, no. 1745, 2023, (Morphology, composition, and uniformity of highly entropic nanoalloys are critical to their properties and applications. Here, the authors develop a DNA origami-based metallization reaction concept for the precise synthesis of multimetallic nanopatterns.).
High-entropy multimetallic nanopatterns with controlled morphology, composition and uniformity hold great potential for developing nanoelectronics, nanophotonics and catalysis. Nevertheless, the lack of general methods for patterning multiple metals poses a limit. Here, we develop a DNA origami-based metallization reaction system to prescribe multimetallic nanopatterns with peroxidase-like activities. We find that strong coordination between metal elements and DNA bases enables the accumulation of metal ions on protruding clustered DNA (pcDNA) that are prescribed on DNA origami. As a result of the condensation of pcDNA, these sites can serve as nucleation site for metal plating. We have synthesized multimetallic nanopatterns composed of up to five metal elements (Co, Pd, Pt, Ag and Ni), and obtained insights on elemental uniformity control at the nanoscale. This method provides an alternative pathway to construct a library of multimetallic nanopatterns.
Fei Nie, Ke-Zhi Wang, Dongpeng Yan
Supramolecular glasses with color-tunable circularly polarized afterglow through evaporation-induced self-assembly of chiral metal–organic complexes
In: Nature Communications, vol. 14, no. 1654, 2023, (Material designs with multicolor circularly polarized emissions are desirable for photonic applications. Here, the authors report supramolecular glasses based on self-assembled chiral metal–organic complexes with color-tunable circularly polarized afterglow.).
The fabrication of chiral molecules into macroscopic systems has many valuable applications, especially in the fields of optical displays, data encryption, information storage, and so on. Here, we design and prepare a serious of supramolecular glasses (SGs) based on Zn-L-Histidine complexes, via an evaporation-induced self-assembly (EISA) strategy. Metal-ligand interactions between the zinc(II) ion and chiral L-Histidine endow the SGs with interesting circularly polarized afterglow (CPA). Multicolored CPA emissions from blue to red with dissymmetry factor as high as 9.5 × 10−3 and excited-state lifetime up to 356.7 ms are achieved under ambient conditions. Therefore, this work not only communicates the bulk SGs with wide-tunable afterglow and large circular polarization, but also provides an EISA method for the macroscopic self-assembly of chiral metal–organic hybrids toward photonic applications.
Maximilian Dreher, Pierre Martin Dombrowski, Matthias Wolfgang Tripp, Niels Münster, Ulrich Koert, Gregor Witte
Shape control in 2D molecular nanosheets by tuning anisotropic intermolecular interactions and assembly kinetics
In: Nature Communications, vol. 14, no. 1554, 2023, (Structuring organic films is of scientific and technological interest. Here, the authors use partially fluorinated organic molecules exhibiting strong intermolecular interactions to form extended 2D molecular nanosheets and control their shape through growth and desorption kinetics.).
Since molecular materials often decompose upon exposure to radiation, lithographic patterning techniques established for inorganic materials are usually not applicable for the fabrication of organic nanostructures. Instead, molecular self-organisation must be utilised to achieve bottom-up growth of desired structures. Here, we demonstrate control over the mesoscopic shape of 2D molecular nanosheets without affecting their nanoscopic molecular packing motif, using molecules that do not form lateral covalent bonds. We show that anisotropic attractive Coulomb forces between partially fluorinated pentacenes lead to the growth of distinctly elongated nanosheets and that the direction of elongation differs between nanosheets that were grown and ones that were fabricated by partial desorption of a complete molecular monolayer. Using kinetic Monte Carlo simulations, we show that lateral intermolecular interactions alone are sufficient to rationalise the different kinetics of structure formation during nanosheet growth and desorption, without inclusion of interactions between the molecules and the supporting MoS2 substrate. By comparison of the behaviour of differently fluorinated molecules, experimentally and computationally, we can identify properties of molecules with regard to interactions and molecular packing motifs that are required for an effective utilisation of the observed effect.
Xiaolin Lu, Xujie Wang, Shuangshuang Wang, Tao Ding
Polarization-directed growth of spiral nanostructures by laser direct writing with vector beams
In: Nature Communications, vol. 14, no. 1422, 2023, (Chiral nanostructures are in demand for various applications, but large-scale fabrication is a technical challenge. Here, the authors report polarization-directed chiral growth of complex spiral patterns by laser direct writing with vector beams.).
Chirality is pivotal in nature which attracts wide research interests from all disciplines and creating chiral matter is one of the central themes for chemists and material scientists. Despite of significant efforts, a simple, cost-effective and general method that can produce different kinds of chiral metamaterials with high regularity and tailorability is still demanding but greatly missing. Here, we introduce polarization-directed growth of spiral nanostructures via vector beams, which is simple, tailorable and generally applicable to both plasmonic and dielectric materials. The self-aligned near field enhances the photochemical growth along the polarization, which is crucial for the oriented growth. The obtained plasmonic chiral nanostructures present prominent optical activity with a g-factor up to 0.4, which can be tuned by adjusting the spirality of the vector beams. These spiral plasmonic nanostructures can be used for the sensing of different chiral enantiomers. The dielectric chiral metasurfaces can also be formed in arrays of sub-mm scale, which exhibit a g-factor over 0.1. However, photoluminescence of chiral cadmium sulfide presents a very weak luminescence g-factor with the excitation of linearly polarized light. A number of applications can be envisioned with these chiral nanostructures such as chiral sensing, chiral separation and chiral information storage.
Yingrui Zhang, Ziwei Ye, Chunchun Li, Qinglu Chen, Wafaa Aljuhani, Yiming Huang, Xin Xu, Chunfei Wu, Steven E. J. Bell, Yikai Xu
General approach to surface-accessible plasmonic Pickering emulsions for SERS sensing and interfacial catalysis
In: Nature Communications, vol. 14, no. 1392, 2023, (The preparation of Pickering emulsions from nanoparticles commonly requires modification of the particles’ surface chemistry. Here, the authors demonstrate a chemical modifier-free approach for the preparation of long-term stable Pickering emulsions for SERS sensing and catalytic applications.).
Pickering emulsions represent an important class of functional materials with potential applications in sustainability and healthcare. Currently, the synthesis of Pickering emulsions relies heavily on the use of strongly adsorbing molecular modifiers to tune the surface chemistry of the nanoparticle constituents. This approach is inconvenient and potentially a dead-end for many applications since the adsorbed modifiers prevent interactions between the functional nanosurface and its surroundings. Here, we demonstrate a general modifier-free approach to construct Pickering emulsions by using a combination of stabilizer particles, which stabilize the emulsion droplet, and a second population of unmodified functional particles that sit alongside the stabilizers at the interface. Freeing Pickering emulsions from chemical modifiers unlocks their potential across a range of applications including plasmonic sensing and interfacial catalysis that have previously been challenging to achieve. More broadly, this strategy provides an approach to the development of surface-accessible nanomaterials with enhanced and/or additional properties from a wide range of nano-building blocks including organic nanocrystals, carbonaceous materials, metals and oxides.
Nan Cao, Biao Yang, Alexander Riss, Johanna Rosen, Jonas Björk, Johannes V. Barth
On-surface synthesis of enetriynes
In: Nature Communications, vol. 14, no. 1255, 2023, (Enetriynes, which belong to the enyne family, are characterized by a distinct electron-rich carbon-bonding scheme. Here, the authors report the formation of enetriynes with high selectivity by tetramerization of terminal alkynes on Ag(100).).
Belonging to the enyne family, enetriynes comprise a distinct electron-rich all-carbon bonding scheme. However, the lack of convenient synthesis protocols limits the associated application potential within, e.g., biochemistry and materials science. Herein we introduce a pathway for highly selective enetriyne formation via tetramerization of terminal alkynes on a Ag(100) surface. Taking advantage of a directing hydroxyl group, we steer molecular assembly and reaction processes on square lattices. Induced by O2 exposure the terminal alkyne moieties deprotonate and organometallic bis-acetylide dimer arrays evolve. Upon subsequent thermal annealing tetrameric enetriyne-bridged compounds are generated in high yield, readily self-assembling into regular networks. We combine high-resolution scanning probe microscopy, X-ray photoelectron spectroscopy and density functional theory calculations to examine the structural features, bonding characteristics and the underlying reaction mechanism. Our study introduces an integrated strategy for the precise fabrication of functional enetriyne species, thus providing access to a distinct class of highly conjugated π-system compounds.
Hongwei Cheng, Xiaoxia Zhu, Xiaowei Cheng, Pengzhan Cai, Jie Liu, Huijun Yao, Ling Zhang, Jinglai Duan
Mechanical metamaterials made of freestanding quasi-BCC nanolattices of gold and copper with ultra-high energy absorption capacity
In: Nature Communications, vol. 14, no. 1243, 2023, (The fabrication of freestanding 3D lattice structures with beam diameters less than 100 nm is a considerable challenge. Here, the authors report quasi-BCC nanolattices of gold and copper, featuring beam diameters as low as 34 nm, that demonstrate an exceptionally high capacity for energy absorption.).
Nanolattices exhibit attractive mechanical properties such as high strength, high specific strength, and high energy absorption. However, at present, such materials cannot achieve effective fusion of the above properties and scalable production, which hinders their applications in energy conversion and other fields. Herein, we report gold and copper quasi-body centered cubic (quasi-BCC) nanolattices with the diameter of the nanobeams as small as 34 nm. We show that the compressive yield strengths of quasi-BCC nanolattices even exceed those of their bulk counterparts, despite their relative densities below 0.5. Simultaneously, these quasi-BCC nanolattices exhibit ultrahigh energy absorption capacities, i.e., 100 ± 6 MJ m−3 for gold quasi-BCC nanolattice and 110 ± 10 MJ m−3 for copper quasi-BCC nanolattice. Finite element simulations and theoretical calculations reveal that the deformation of quasi-BCC nanolattice is dominated by nanobeam bending. And the anomalous energy absorption capacities substantially stem from the synergy of the naturally high mechanical strength and plasticity of metals, the size reduction-induced mechanical enhancement, and the quasi-BCC nanolattice architecture. Since the sample size can be scaled up to macroscale at high efficiency and affordable cost, the quasi-BCC nanolattices with ultrahigh energy absorption capacity reported in this work may find great potentials in heat transfer, electric conduction, catalysis applications.
Rozeline Wijnhorst, Menno Demmenie, Etienne Jambon-Puillet, Freek Ariese, Daniel Bonn, Noushine Shahidzadeh
Softness of hydrated salt crystals under deliquescence
In: Nature Communications, vol. 14, no. 1090, 2023, (Crystals are commonly associated with their hard and faceted nature. Here, the authors report the transition from hard to soft and deformable, observed in the gradual dissolution of salt crystals that harbor water in their crystalline framework.).
Deliquescence is a first-order phase transition, happening when a salt absorbs water vapor. This has a major impact on the stability of crystalline powders that are important for example in pharmacology, food science and for our environment and climate. Here we show that during deliquescence, the abundant salt sodium sulfate decahydrate, mirabilite (Na2SO4·10H2O), behaves differently than anhydrous salts. Using various microscopy techniques combined with Raman spectroscopy, we show that mirabilite crystals not only lose their facets but also become soft and deformable. As a result, microcrystals of mirabilite simultaneously behave crystalline-like in the core bulk and liquid-like at the surface. Defects at the surface can heal at a speed much faster than the deliquescence rate by the mechanism of visco-capillary flow over the surface. While magnesium sulfate hexahydrate (MgSO4⋅6H2O) behaves similarly during deliquescence, a soft and deformable state is completely absent for the anhydrous salts sodium chloride (NaCl) and sodium sulfate thenardite (Na2SO4). The results highlight the effect of crystalline water, and its mobility in the crystalline structure on the observed softness during deliquescence. Controlled hydrated salts have potential applications such as thermal energy storage, where the key parameter is relative humidity rather than temperature.
Massimo Bocus, Ruben Goeminne, Aran Lamaire, Maarten Cools-Ceuppens, Toon Verstraelen, Veronique Van Speybroeck
Nuclear quantum effects on zeolite proton hopping kinetics explored with machine learning potentials and path integral molecular dynamics
In: Nature Communications, vol. 14, no. 1008, 2023, (The quantum properties of hydrogen atoms in zeolite-catalyzed reactions are generally neglected due to high computational costs. Here, the authors leverage machine learning to derive accurate quantum kinetics for proton transfer reactions in heterogeneous catalysis.).
Proton hopping is a key reactive process within zeolite catalysis. However, the accurate determination of its kinetics poses major challenges both for theoreticians and experimentalists. Nuclear quantum effects (NQEs) are known to influence the structure and dynamics of protons, but their rigorous inclusion through the path integral molecular dynamics (PIMD) formalism was so far beyond reach for zeolite catalyzed processes due to the excessive computational cost of evaluating all forces and energies at the Density Functional Theory (DFT) level. Herein, we overcome this limitation by training first a reactive machine learning potential (MLP) that can reproduce with high fidelity the DFT potential energy surface of proton hopping around the first Al coordination sphere in the H-CHA zeolite. The MLP offers an immense computational speedup, enabling us to derive accurate reaction kinetics beyond standard transition state theory for the proton hopping reaction. Overall, more than 0.6 μs of simulation time was needed, which is far beyond reach of any standard DFT approach. NQEs are found to significantly impact the proton hopping kinetics up to ~473 K. Moreover, PIMD simulations with deuterium can be performed without any additional training to compute kinetic isotope effects over a broad range of temperatures.
Jacob I. Deneff, Lauren E. S. Rohwer, Kimberly S. Butler, Bryan Kaehr, Dayton J. Vogel, Ting S. Luk, Raphael A. Reyes, Alvaro A. Cruz-Cabrera, James E. Martin, Dorina F. Sava Gallis
Orthogonal luminescence lifetime encoding by intermetallic energy transfer in heterometallic rare-earth MOFs
In: Nature Communications, vol. 14, no. 981, 2023, (Lifetime-encoded materials are attractive as optical markers. Here, the authors report a design strategy for true orthogonality in encoding based on heterometallic rare-earth MOFs with independently variable lifetime and composition.).
Lifetime-encoded materials are particularly attractive as optical tags, however examples are rare and hindered in practical application by complex interrogation methods. Here, we demonstrate a design strategy towards multiplexed, lifetime-encoded tags via engineering intermetallic energy transfer in a family of heterometallic rare-earth metal-organic frameworks (MOFs). The MOFs are derived from a combination of a high-energy donor (Eu), a low-energy acceptor (Yb) and an optically inactive ion (Gd) with the 1,2,4,5 tetrakis(4-carboxyphenyl) benzene (TCPB) organic linker. Precise manipulation of the luminescence decay dynamics over a wide microsecond regime is achieved via control over metal distribution in these systems. Demonstration of this platform’s relevance as a tag is attained via a dynamic double encoding method that uses the braille alphabet, and by incorporation into photocurable inks patterned on glass and interrogated via digital high-speed imaging. This study reveals true orthogonality in encoding using independently variable lifetime and composition, and highlights the utility of this design strategy, combining facile synthesis and interrogation with complex optical properties.
Sabrina D. Eder, Adam Fahy, Matthew G. Barr, J. R. Manson, Bodil Holst, Paul C. Dastoor
Sub-resolution contrast in neutral helium microscopy through facet scattering for quantitative imaging of nanoscale topographies on macroscopic surfaces
In: Nature Communications, vol. 14, no. 904, 2023, (Neutral helium microscopy is a completely nondestructive, surface-sensitive imaging technique. Here, the authors demonstrate sub-resolution contrast using an advanced facet scattering model to reconstruct the topography of technological thin films in the ångström range.).
Nanoscale thin film coatings and surface treatments are ubiquitous across industry, science, and engineering; imbuing specific functional or mechanical properties (such as corrosion resistance, lubricity, catalytic activity and electronic behaviour). Non-destructive nanoscale imaging of thin film coatings across large (ca. centimetre) lateral length scales, crucial to a wide range of modern industry, remains a significant technical challenge. By harnessing the unique nature of the helium atom–surface interaction, neutral helium microscopy images these surfaces without altering the sample under investigation. Since the helium atom scatters exclusively from the outermost electronic corrugation of the sample, the technique is completely surface sensitive. Furthermore, with a cross-section that is orders of magnitude larger than that of electrons, neutrons and photons, the probe particle routinely interacts with features down to the scale of surface defects and small adsorbates (including hydrogen). Here, we highlight the capacity of neutral helium microscopy for sub-resolution contrast using an advanced facet scattering model based on nanoscale features. By replicating the observed scattered helium intensities, we demonstrate that sub-resolution contrast arises from the unique surface scattering of the incident probe. Consequently, it is now possible to extract quantitative information from the helium atom image, including localised ångström-scale variations in topography.
Yi Yang, Jong Bin Kim, Seong Kyeong Nam, Mengmeng Zhang, Jiangping Xu, Jintao Zhu, Shin-Hyun Kim
Nanostructure-free crescent-shaped microparticles as full-color reflective pigments
In: Nature Communications, vol. 14, no. 793, 2023, (Structural colors arise from nanostructures or special microgeometries. Here, the authors report on crescent-shaped microparticles as full-color reflective pigments that show brilliant colors in directional light and are transparent in ambient light.).
Structural colors provide a promising visualization with high color saturation, iridescent characteristics, and fade resistance. However, pragmatic uses are frequently impeded by complex manufacturing processes for sophisticated nanostructures. Here, we report a facile emulsion-templating strategy to produce crescent-shaped microparticles as structural color pigments. The micro-crescents exhibit brilliant colors under directional light originating from total internal reflections and optical interferences in the absence of periodic nanostructures while being transparent under ambient light. The colors are finely tunable by adjusting the size of the micro-crescents, which can be further mixed to enrich the variety. Importantly, the pre-defined convex surface secures high stability of colors and enables structural coloration on target surfaces through direct deposition as inks. We anticipate this class of nanostructure-free structural colorants is pragmatic as invisible inks in particular for anti-counterfeiting patches and color cosmetics with distinctive impressions due to low-cost, scalable manufacturing, unique optical properties, and versatility.
Yuan Zhong, Jiangwei Zhang, Tingting Li, Wenwu Xu, Qiaofeng Yao, Min Lu, Xue Bai, Zhennan Wu, Jianping Xie, Yu Zhang
Suppression of kernel vibrations by layer-by-layer ligand engineering boosts photoluminescence efficiency of gold nanoclusters
In: Nature Communications, vol. 14, no. 658, 2023, (The photoluminescence of gold nanoclusters is affected by low-frequency acoustic vibrations. Here, the authors demonstrate that layer-by-layer ligand engineering can suppress such structural vibrations to achieve brighter emissions.).
The restriction of structural vibration has assumed great importance in attaining bright emission of luminescent metal nanoclusters (NCs), where tremendous efforts are devoted to manipulating the surface landscape yet remain challenges for modulation of the structural vibration of the metal kernel. Here, we report efficient suppression of kernel vibration achieving enhancement in emission intensity, by rigidifying the surface of metal NCs and propagating as-developed strains into the metal core. Specifically, a layer-by-layer triple-ligands surface engineering is deployed to allow the solution-phase Au NCs with strong metal core-dictated fluorescence, up to the high absolute quantum yields of 90.3 ± 3.5%. The as-rigidified surface imposed by synergistic supramolecular interactions greatly influences the low-frequency acoustic vibration of the metal kernel, resulting in a subtle change in vibration frequency but a reduction in amplitude of oscillation. This scenario therewith impedes the non-radiative relaxation of electron dynamics, rendering the Au NCs with strong emission. The presented study exemplifies the linkage between surface chemistry and core-state emission of metal NCs, and proposes a strategy for brighter emitting metal NCs by regulating their interior metal core-involved motion.
Yong Chen, Satoshi Takeya, Amadeu K. Sum
Topological dual and extended relations between networks of clathrate hydrates and Frank-Kasper phases
In: Nature Communications, vol. 14, no. 596, 2023, (Topological dual and extended relations between networks of clathrate hydrates and Frank-Kasper phases Clathrate hydrates are topological duals of Frank-Kasper phases. Here, the authors employ MD simulations to provide an alternative way to explore the intrinsic structural relationships of H-bonded networks of clathrate hydrates and other unrelated ordered materials.).
Clathrate hydrates are a class of ordered structures that are stabilized via the delicate balance of hydrophobic interactions between water and guest molecules, of which the space-filling network of hydrogen-bonded (H-bonded) water molecules are closely related to tetrahedrally close-packed structures, known as Frank-Kasper (FK) phases. Here we report an alternative way to understand the intricate structures of clathrate hydrates, which unveils the diverse crystalline H-bonded networks that can be generated via assembly of one common building block. In addition to the intrinsic relations and pathways linking these crystals, we further illustrate the rich structural possibilities of clathrate hydrates. Given that the topological dual relations between networks of clathrate hydrates and tetrahedral close-packed structures, the descriptors presented for clathrate hydrates can be directly extended to other ordered materials for a more thorough understanding of their nucleation, phases transition, and co-existence mechanisms.
Ahmed A. Agiza, Kady Oakley, Jacob K. Rosenstein, Brenda M. Rubenstein, Eunsuk Kim, Marc Riedel, Sherief Reda
Digital circuits and neural networks based on acid-base chemistry implemented by robotic fluid handling
In: Nature Communications, vol. 14, no. 496, 2023, (The complementarity of acids and bases is a fundamental chemical concept. Here, the authors use simple acid-base chemistry to encode binary information and perform information processing including digital circuits and neural networks using robotic fluid handling.).
Acid-base reactions are ubiquitous, easy to prepare, and execute without sophisticated equipment. Acids and bases are also inherently complementary and naturally map to a universal representation of “0” and “1.” Here, we propose how to leverage acids, bases, and their reactions to encode binary information and perform information processing based upon the majority and negation operations. These operations form a functionally complete set that we use to implement more complex computations such as digital circuits and neural networks. We present the building blocks needed to build complete digital circuits using acids and bases for dual-rail encoding data values as complementary pairs, including a set of primitive logic functions that are widely applicable to molecular computation. We demonstrate how to implement neural network classifiers and some classes of digital circuits with acid-base reactions orchestrated by a robotic fluid handling device. We validate the neural network experimentally on a number of images with different formats, resulting in a perfect match to the in-silico classifier. Additionally, the simulation of our acid-base classifier matches the results of the in-silico classifier with approximately 99% similarity.
Jeonghee Yeom, Ayoung Choe, Jiyun Lee, Jeeyoon Kim, Jinyoung Kimand Seung Hak Ohand Cheolhong Park, Sangyun Naand Young-Eun Shinand Youngoh Lee, Yun Goo Ro, Sang Kyu Kwak, Hyunhyub Ko
Photosensitive ion channels in layered MXene membranes modified with plasmonic gold nanostars and cellulose nanofibers
In: Nature Communications, vol. 14, no. 359, 2023, (Artificial ion channels are in demand for ionotronic devices. Here, the authors use layered MXene membranes modified with plasmonic gold nanostars and cellulose nanofibers to convert a thermal gradient into an ion current for photosensitive ion channeling.).
Ion channels transduce external stimuli into ion-transport-mediated signaling, which has received considerable attention in diverse fields such as sensors, energy harvesting devices, and desalination membrane. In this work, we present a photosensitive ion channel based on plasmonic gold nanostars (AuNSs) and cellulose nanofibers (CNFs) embedded in layered MXene nanosheets. The MXene/AuNS/CNF (MAC) membrane provides subnanometer-sized ionic pathways for light-sensitive cationic flow. When the MAC nanochannel is exposed to NIR light, a photothermal gradient is formed, which induces directional photothermo-osmotic flow of nanoconfined electrolyte against the thermal gradient and produces a net ionic current. MAC membrane exhibits enhanced photothermal current compared with pristine MXene, which is attributed to the combined photothermal effects of plasmonic AuNSs and MXene and the widened interspacing of the MAC composite via the hydrophilic nanofibrils. The MAC composite membranes are envisioned to be applied in flexible ionic channels with ionogels and light-controlled ionic circuits.
Michael Moret, Irene Pachon Angona, Leandro Cotos, Shen Yan, Kenneth Atz, Cyrill Brunner, Martin Baumgartner, Francesca Grisoni, Gisbert Schneider
Leveraging molecular structure and bioactivity with chemical language models for de novo drug design
In: Nature Communications, vol. 14, no. 114, 2023, (Generative Deep Learning holds promise for mining the unexplored "chemical universe" for new drugs. Here, the authors demonstrate the de novo design of phosphoinositide 3-kinase gamma (PI3Kγ) inhibitors for the PI3K/Akt pathway in human tumor cells.).
Generative chemical language models (CLMs) can be used for de novo molecular structure generation by learning from a textual representation of molecules. Here, we show that hybrid CLMs can additionally leverage the bioactivity information available for the training compounds. To computationally design ligands of phosphoinositide 3-kinase gamma (PI3Kγ), a collection of virtual molecules was created with a generative CLM. This virtual compound library was refined using a CLM-based classifier for bioactivity prediction. This second hybrid CLM was pretrained with patented molecular structures and fine-tuned with known PI3Kγ ligands. Several of the computer-generated molecular designs were commercially available, enabling fast prescreening and preliminary experimental validation. A new PI3Kγ ligand with sub-micromolar activity was identified, highlighting the method’s scaffold-hopping potential. Chemical synthesis and biochemical testing of two of the top-ranked de novo designed molecules and their derivatives corroborated the model’s ability to generate PI3Kγ ligands with medium to low nanomolar activity for hit-to-lead expansion. The most potent compounds led to pronounced inhibition of PI3K-dependent Akt phosphorylation in a medulloblastoma cell model, demonstrating efficacy of PI3Kγ ligands in PI3K/Akt pathway repression in human tumor cells. The results positively advocate hybrid CLMs for virtual compound screening and activity-focused molecular design.
Yingying Jiang, Martial Duchamp, Shi Jun Ang, Hongwei Yan, Teck Leong Tan, Utkur Mirsaidov
Dynamics of the fcc-to-bcc phase transition in single-crystalline PdCu alloy nanoparticles
In: Nature Communications, vol. 14, no. 104, 2023, (Phase transitions in crystals are challenging to study with atomic resolution. Here, the authors reveal that the transition from fcc to bcc occurs across a coherent interface only a few atoms wide, which serves as a precursor phase for the nucleation of the bcc phase.).
Two most common crystal structures in metals and metal alloys are body-centered cubic (bcc) and face-centered cubic (fcc) structures. The phase transitions between these structures play an important role in the production of durable and functional metal alloys. Despite their technological significance, the details of such phase transitions are largely unknown because of the challenges associated with probing these processes. Here, we describe the nanoscopic details of an fcc-to-bcc phase transition in PdCu alloy nanoparticles (NPs) using in situ heating transmission electron microscopy. Our observations reveal that the bcc phase always nucleates from the edge of the fcc NP, and then propagates across the NP by forming a distinct few-atoms-wide coherent bcc–fcc interface. Notably, this interface acts as an intermediate precursor phase for the nucleation of a bcc phase. These insights into the fcc-to-bcc phase transition are important for understanding solid − solid phase transitions in general and can help to tailor the functional properties of metals and their alloys.
Tonghan Zhao, Dejing Meng, Zhijian Hu, Wenjing Sun, Yinglu Ji, Jianlei Han, Xue Jin, Xiaochun Wu, Pengfei Duan
Enhanced chiroptic properties of nanocomposites of achiral plasmonic nanoparticles decorated with chiral dye-loaded micelles
In: Nature Communications, vol. 14, no. 81, 2023, (Circularly polarized luminescent materials with large dissymmetry and efficiency are in demand. Here, the authors investigate chirality-induced spin polarization in achiral gold nanorods decorated with chiral dye-loaded micelles to enhance chiroptic activity.).
The development of circularly polarized luminescence (CPL)-active materials with both large luminescence dissymmetry factor (glum) and high emission efficiency continues to be a major challenge. Here, we present an approach to improve the overall CPL performance by integrating triplet-triplet annihila- tion-based photon upconversion (TTA-UC) with localized surface plasmon resonance. Dye-loaded chiral micelles possessing TTA-UC ability are designed and attached on the surface of achiral gold nanorods (AuNRs). The long- itudinal and transversal resonance peaks of AuNRs overlap with the absorption and emission of dye-loaded chiral micelles, respectively. Typically, 43-fold amplification of glum value accompanied by 3-fold enhancement of upcon- version are obtained simultaneously when Au@Ag nanorods are employed in the composites. More importantly, transient absorption spectra reveal a fast accumulation of spin-polarized triplet excitons in the composites. Therefore, the enhancement of chirality-induced spin polarization should be in charge of the amplification of glum value. Our design strategy suggests that combining plasmonic nanomaterials with chiral organic materials could aid in the devel- opment of chiroptical nanomaterials.
Pengwei Xiao, Zhoufan Zhang, Junjun Ge, Yalei Deng, Xufeng Chen, Jian-Rong Zhang, Zhengtao Deng, Yu Kambe, Dmitri V. Talapin, Yuanyuan Wang
Surface passivation of intensely luminescent all-inorganic nanocrystals and their direct optical patterning
In: Nature Communications, vol. 14, no. 49, 2023, (All-inorganic nanocrystals are of great importance for a variety of electronic applications. Here, the authors use metal salts to remove organic ligands to obtain passivated nanocrystals with improved fluorescence yield for direct optical patterning.).
All-inorganic nanocrystals (NCs) are of great importance in a range of electronic devices. However, current all-inorganic NCs suffer from limitations in their optical properties, such as low fluorescence efficiencies. Here, we develop a general surface treatment strategy to obtain intensely luminescent all-inorganic NCs (ILANs) by using designed metal salts with noncoordinating anions that play a dual role in the surface treatment process: (i) removing the original organic ligands and (ii) binding to unpassivated Lewis basic sites to preserve the photoluminescent (PL) properties of the NCs. The absolute photoluminescence quantum yields (PLQYs) of red-emitting CdSe/ZnS NCs, green-emitting CdSe/CdZnSeS/ZnS NCs and blue-emitting CdZnS/ZnS NCs in polar solvents are 97%, 80% and 72%, respectively. Further study reveals that the passivated Lewis basic sites of ILANs by metal cations boost the efficiency of radiative recombination of electron-hole pairs. While the passivation of Lewis basic sites leads to a high PLQY of ILANs, the exposed Lewis acidic sites provide the possibility for in situ tuning of the functions of NCs, creating opportunities for direct optical patterning of functional NCs with high resolution.
Yeongho Choi, Donghyo Hahm, Wan Ki Bae, Jaehoon Lim
Heteroepitaxial chemistry of zinc chalcogenides on InP nanocrystals for defect-free interfaces with atomic uniformity
In: Nature Communications, vol. 14, no. 43, 2023, (Heteroepitaxy on colloidal nanocrystals often yields defective heterostructures due to intricate reaction pathways. Here, the authors decode the surface chemistry at the molecular level to realize defect-free interfaces with atomic uniformity.).
Heteroepitaxy on colloidal semiconductor nanocrystals is an essential strategy for manipulating their optoelectronic functionalities. However, their practical synthesis typically leads to scattered and unexpected outcomes due to the intervention of multiple reaction pathways associated with complicated side products of reactants. Here, the heteroepitaxy mechanism of zinc chalcogenide initiated on indium phosphide (InP) colloidal nanocrystals is elucidated using the precursors, zinc carboxylate and trialkylphosphine selenide. The high magnetic receptivity of 77Se and the characteristic longitudinal optical phonon mode of ZnSe allowed for monitoring the sequence of epilayer formation at the molecular level. The investigation revealed the sterically hindered acyloxytrialkylphosphonium and diacyloxytrialkylphosphorane to be main intermediates in the surface reaction, which retards the metal ion adsorption by a large steric hindrance. The transformation of adsorbates to the crystalline epilayer was disturbed by surface oxides. Raman scattering disclosed the pathway of secondary surface oxidation triggered by carboxylate ligands migrated from zinc carboxylate. The surface-initiated heteroepitaxy protocol is proposed to fabricate core/shell heterostructured nanocrystals with atomic-scale uniformity of epilayers. Despite the large lattice mismatch of ZnS to InP, we realised a uniform and interface defect-free ZnS epilayer (~0.3 nm thickness) on InP nanocrystals, as evidenced by a high photoluminescence quantum yield of 97.3%.
Yilong Zhou, Gaurav Arya
Discovery of two-dimensional binary nanoparticle superlattices using global Monte Carlo optimization
In: Nature Communications, vol. 13, no. 7976, 2022, (Binary nanoparticle superlattices exhibit different collective optical, magnetic, and electronic properties. Here, the authors develop an efficient global optimization algorithm for the discovery of periodic 2D architectures forming at fluid interfaces.).
Binary nanoparticle (NP) superlattices exhibit distinct collective plasmonic, magnetic, optical, and electronic properties. Here, we computationally demonstrate how fluid-fluid interfaces could be used to self-assemble binary systems of NPs into 2D superlattices when the NP species exhibit different miscibility with the fluids forming the interface. We develop a basin-hopping Monte Carlo (BHMC) algorithm tailored for interface-trapped structures to rapidly determine the ground-state configuration of NPs, allowing us to explore the repertoire of binary NP architectures formed at the interface. By varying the NP size ratio, interparticle interaction strength, and difference in NP miscibility with the two fluids, we demonstrate the assembly of an array of exquisite 2D periodic architectures, including AB-, AB2-, and AB3-type monolayer superlattices as well as AB-, AB2-, A3B5-, and A4B6-type bilayer superlattices. Our results suggest that the interfacial assembly approach could be a versatile platform for fabricating 2D colloidal superlattices with tunable structure and properties.
Xueyan Chen, Qianqian Ding, Chao Bi, Jian Ruan, Shikuan Yang
Lossless enrichment of trace analytes in levitating droplets for multiphase and multiplex detection
In: Nature Communications, vol. 13, no. 7807, 2022, (Efficient enrichment of molecules from liquids, solid objects, or the gas phase is critical for their detection at trace concentrations. Here, the authors report on the lossless enrichment of analytes in droplets using acoustic levitation for multiphase and multiplex SERS detection.).
Concentrating a trace amount of molecules from liquids, solid objects, or the gas phase and delivering them to a localized area are crucial for almost any trace analyte detection device. Analytes within a liquid droplet resting on micro/nanostructured surfaces with liquid-repellent coatings can be concentrated during solvent evaporation. However, these coatings suffer from complex manufacturing procedures, poor versatility, and limited analyte enrichment efficiency. Here, we report on the use of an acoustic levitation platform to losslessly concentrate the analyte molecules dissolved in any volatile liquid, attached to solid objects, or spread in air. Gold nanoparticles can be simultaneously concentrated with the analytes in different phases, realizing sensitive, surface-enhanced Raman scattering detection even at attomolar (10^−18 mol/L) concentration levels. The acoustic levitation platform-enabled, lossless analyte enrichment can significantly increase the analytical performance of many conventional microsensing techniques.
Xinquan Zhou, Lixin Ning, Jianwei Qiao, Yifei Zhao, Puxian Xiong, Zhiguo Xia
Interplay of defect levels and rare earth emission centers in multimode luminescent phosphors
In: Nature Communications, vol. 13, no. 7589, 2022, (Information encryption technology calls for versatile multi-mode luminescent materials. Here, the authors develop phosphors with five integrated luminescence modes by exploiting the interplay of defect levels and rare-earth emission centers.).
Multimode luminescence generally involves tunable photon emissions in response to various excitation or stimuli channels, which demonstrates high coding capacity and confidentiality abilities for anti-counterfeiting and encryption technologies. Integrating multimode luminescence into a single stable material is a promising strategy but remains a challenge. Here, we realize distinct long persistent luminescence, short-lived down/upconversion emissions in NaGdTi2O6:Pr3+, Er3+ phosphor by emloying interplay of defect levels and rare earth emission centers. The materials show intense colorful luminescence statically and dynamically, which responds to a wide spectrum ranging from X-ray to sunlight, thermal disturbance, and mechanical force, further allowing the emission colors manipulable in space and time dimensions. Experimental and theoretical approaches reveal that the Pr3+ ↔ Pr4+ valence change, oxygen vacancies and anti-site TiGd defects in this disordered structure contributes to the multimode luminescence. We present a facile and nondestructive demo whose emission color and fade intensity can be controlled via external manipulation, indicating promise in high-capacity information encryption applications.
I-Ju Chen, Markus Aapro, Abraham Kipnis, Alexander Ilin, Peter Liljeroth, Adam S. Foster
Precise atom manipulation through deep reinforcement learning
In: Nature Communications, vol. 13, no. 7499, 2022, (Engineering quantum states requires precise manipulations at the atomic level. Here, the authors use deep reinforcement learning to manipulate Ag adatoms on Ag surfaces, which combined with path planning algorithms enables autonomous atomic assembly.).
Atomic-scale manipulation in scanning tunneling microscopy has enabled the creation of quantum states of matter based on artificial structures and extreme miniaturization of computational circuitry based on individual atoms. The ability to autonomously arrange atomic structures with precision will enable the scaling up of nanoscale fabrication and expand the range of artificial structures hosting exotic quantum states. However, the a priori unknown manipulation parameters, the possibility of spontaneous tip apex changes, and the difficulty of modeling tip-atom interactions make it challenging to select manipulation parameters that can achieve atomic precision throughout extended operations. Here we use deep reinforcement learning (DRL) to control the real-world atom manipulation process. Several state-of-the-art reinforcement learning (RL) techniques are used jointly to boost data efficiency. The DRL agent learns to manipulate Ag adatoms on Ag(111) surfaces with optimal precision and is integrated with path planning algorithms to complete an autonomous atomic assembly system. The results demonstrate that state-of-the-art DRL can offer effective solutions to real-world challenges in nanofabrication and powerful approaches to increasingly complex scientific experiments at the atomic scale.
Shuzhen Yan, Kaiming Hu, Shuai Chen, Tiantian Li, Wenming Zhang, Jie Yin, Xuesong Jiang
Photo-induced stress relaxation in reconfigurable disulfide-crosslinked supramolecular films visualized by dynamic wrinkling
In: Nature Communications, vol. 13, no. 7434, 2022, (The mechanics of reconfigurable supramolecular polymer networks are governed by their dynamic crosslinking chemistry and the resulting stress relaxations. Here, the authors use reversible wrinkling patterns to visualize localized stress relaxations, due to molecular network rearrangements.).
Stress relaxation in reconfigurable supramolecular polymer networks is strongly related to intermolecular behavior. However, the relationship between molecular motion and macroscopic mechanics is usually vague, and the visualization of internal stress reflecting precise regulation of molecules remains challenging. Here, we present a strategy for visualizing photo-driven stress relaxation induced by infinitesimal perturbations in the intermolecular exchange reaction via reprogrammable wrinkle patterns. The supramolecular films exhibit visible changes in microscopic wrinkle topography through ultraviolet (UV)-induced dynamic disulfide exchange reaction. In accordance with the trans-scale theoretical models, which quantitatively evaluate the chemical-dependent mechanical stresses in the supramolecular network, the unexposed disordered wrinkles evolved into highly oriented patterns and underwent subsequent mutations after thermal treatment. The stress-sensitive wrinkle macro-patterns can be repetitively written/erased through network topology rearrangement using different stimuli. This strategy provides an approach for visualizing and understanding the molecular behavior from dynamic chemistry to mechanical changes, and directly programming wrinkle patterns with regulated structures.
Bang Lin Li, Jun Jiang Luo, Hao Lin Zou, Qing-Meng Zhang, Liu-Bin Zhao, Hang Qian, Hong Qun Luo, David Tai Leong, Nian Bing Li
Chiral nanocrystals grown from MoS2 nanosheets enable photothermally modulated enantioselective release of antimicrobial drugs
In: Nature Communications, vol. 13, no. 7289, 2022, (Chirality transfer from molecules to nanomaterials enables advanced optical functionalities. Here, the authors use exfoliated MoS2 nanosheets to seed the growth of chiral Au nanoparticles to form Au/MoS2 heterostructures for enantioselective drug release.).
The transfer of the concept of chirality from molecules to synthesized nanomaterials has attracted attention amongst multidisciplinary teams. Here we demonstrate heterogeneous nucleation and anisotropic accumulation of Au nanoparticles on multilayer MoS2 planes to form chiroptically functional nanomaterials. Thiol amino acids with chiral conformations modulate asymmetric growth of gold nanoarchitectures on seeds of highly faceted Au/MoS2 heterostructures. Consequently, dendritic plasmonic nanocrystals with partial chiral morphologies are synthesized. The chirality of dendritic nanocrystals inherited from cysteine molecules refers to the structural characteristics and includes specific recognition of enantiomeric molecules. With integration of the intrinsic photothermal properties and inherited enantioselective characteristics, dendritic Au/MoS2 heterostructures exhibit chirality-dependent release of antimicrobial drugs from hydrogel substrates when activated by exogenous infrared irradiation. A three-in-one strategy involving synthesis of chiral dendritic heterostructures, enantioselective recognition, and controlled drug release system is presented, which improves nanomaterial synthetic technology and enhances our understanding of crucial chirality information.
Siqi Yu, Yu Du, Xianghong Niu, Guangming Li, Da Zhu, Qian Yu, Guizheng Zou, Huangxian Ju
Arginine-modified black phosphorus quantum dots with dual excited states for enhanced electrochemiluminescence in bioanalysis
In: Nature Communications, vol. 13, no. 7302, 2022, (Electrochemiluminescence is emitted via the radiative transition of a singlet or triplet excited state. Here, the authors propose an arginine modification of black phosphorus quantum dots that exhibits enhanced emission based on dual excited states.).
The electrochemiluminescence (ECL) is generally emitted via radiative transition of singlet or triplet excited state (S1 or T1). Herein, an ECL mechanism with the transitions of both S1 and T1 of black phosphorus quantum dots (BPQDs) is found, and an arginine (Arg) modification strategy is proposed to passivate the surface oxidation defects of BPQDs, which could modulate the excited states for enhancing the ECL efficiency of BPQDs. The Arg modification leads to greater spatial overlap of highest and lowest occupied molecular orbitals, and spectral shift of radiative transitions, and improves the stability of anion radical of BPQDs. To verify the application of the proposed mechanism, it is used to construct a sensitive method for conveniently evaluating the inhibiting efficiency of cyclo-arginine-glycine-aspartic acid-d-tyrosine-lysine to cell surface integrin by using Arg containing peptide modified BPQDs as signal tag. The dual excited states mediated ECL emitters provide a paradigm for adjustable ECL generation and extend the application of ECL analysis.
Qingyu Meng, Laura Abella, Yang-Rong Yao, Dumitru-Claudiu Sergentu, Wei Yang, Xinye Liu, Jiaxin Zhuang, Luis Echegoyen, Jochen Autschbach, Ning Chen
A charged diatomic triple-bonded U≡N species trapped in C82 fullerene cages
In: Nature Communications, vol. 13, no. 7192, 2022, (Diatomic actinide molecules are ideal models for studying rare multiple-bond motifs. Here, the authors report host-guest structures of metastable charged U≡N diatoms confined in fullerene cages and stabilized by coordinative electron transfer.).
Actinide diatomic molecules are ideal models to study elusive actinide multiple bonds, but most of these diatomic molecules have so far only been studied in solid inert gas matrices. Herein, we report a charged U≡N diatomic species captured in fullerene cages and stabilized by the U-fullerene coordination interaction. Two diatomic clusterfullerenes, viz. UN@Cs(6)-C82 and UN@C2(5)-C82, were successfully synthesized and characterized. Crystallographic analysis reveals U-N bond lengths of 1.760(7) and 1.760(20) Å in UN@Cs(6)-C82 and UN@C2(5)-C82. Moreover, U≡N was found to be immobilized and coordinated to the fullerene cages at 100 K but it rotates inside the cage at 273 K. Quantum-chemical calculations show a (UN)2+@(C82)2− electronic structure with formal +5 oxidation state (f1) of U and unambiguously demonstrate the presence of a U≡N bond in the clusterfullerenes. This study constitutes an approach to stabilize fundamentally important actinide multiply bonded species.
Yuanzhi Xia, Semih Sevim, João Pedro Vale, Johannes Seibel, David Rodríguez-San-Miguel, Donghoon Kim, Salvador Pané, Tiago Sotto Mayor, Steven De Feyter, Josep Puigmartí-Luis
Covalent transfer of chemical gradients onto a graphenic surface with 2D and 3D control
In: Nature Communications, vol. 13, no. 7006, 2022, (Covalent modification is an essential chemical method for altering the physicochemical properties of material interfaces. Here, the authors show that the no-slip conditions in microfluidic devices grant spatiotemporal control over molecular grafting.).
Control over the functionalization of graphenic materials is key to enable their full application in electronic and optical technologies. Covalent functionalization strategies have been proposed as an approach to tailor the interfaces’ structure and properties. However, to date, none of the proposed methods allow for a covalent functionalization with control over the grafting density, layer thickness and/or morphology, which are key aspects for fine-tuning the processability and performance of graphenic materials. Here, we show that the no-slip boundary condition at the walls of a continuous flow microfluidic device offers a way to generate controlled chemical gradients onto a graphenic material with 2D and 3D control, a possibility that will allow the sophisticated functionalization of these technologically-relevant materials.
Qianqian Fu, Wenyuan Yu, Guangyang Bao, Jianping Ge
Electrically responsive photonic crystals with bistable states for low-power electrophoretic color displays
In: Nature Communications, vol. 13, no. 7007, 2022, (Conventional electrophoretic color displays require a permanent electric field, increasing power consumption. Here, the authors report an electrically responsive photonic crystal with switchable bistable states by particle rearrangement for low power consumption displays.).
Electrically responsive photonic crystals are promising materials for electrophoretic color displays with better brightness and color saturation. However, electric field must always be applied to maintain the specific colors, which brings concerns about the power consumption and signal stability and reversibility. Here, we show an electrically responsive photonic crystal with two stable states at 0 V, which are the colored state or the colorless state with ordered or disordered particle arrangement. The color state can be reversibly switched by applying a short-time electrical field, just like in the case of commercial electrophoretic ink. With optimized recipe and electric field, the photonic crystals encapsulated in the prototype display panel are proved to have potentials in high resolution, multi-color, and greyscale display, which lays down a firm basis for reflective displays with low power consumption and good visibility.
Ahyoung Kim, Thi Vo, Hyosung An, Progna Banerjee, Lehan Yao, Shan Zhou, Chansong Kim, Delia J. Milliron, Sharon C. Glotzer, Qian Chen
Symmetry-breaking in patch formation on triangular gold nanoparticles by asymmetric polymer grafting
In: Nature Communications, vol. 13, no. 6774, 2022, (Patchy nanoparticles are desirable building blocks for the guided assembly of functional superstructures. Here, the authors demonstrate quantitative control over asymmetric polymer grafting on triangular Au nanoprisms based on polymer scaling theory.).
Synthesizing patchy particles with predictive control over patch size, shape, placement and number has been highly sought-after for nanoparticle assembly research, but is fraught with challenges. Here we show that polymers can be designed to selectively adsorb onto nanoparticle surfaces already partially coated by other chains to drive the formation of patchy nanoparticles with broken symmetry. In our model system of triangular gold nanoparticles and polystyrene-b-polyacrylic acid patch, single- and double-patch nanoparticles are produced at high yield. These asymmetric single-patch nanoparticles are shown to assemble into self-limited patch‒patch connected bowties exhibiting intriguing plasmonic properties. To unveil the mechanism of symmetry-breaking patch formation, we develop a theory that accurately predicts our experimental observations at all scales—from patch patterning on nanoparticles, to the size/shape of the patches, to the particle assemblies driven by patch‒patch interactions. Both the experimental strategy and theoretical prediction extend to nanoparticles of other shapes such as octahedra and bipyramids. Our work provides an approach to leverage polymer interactions with nanoscale curved surfaces for asymmetric grafting in nanomaterials engineering.
Pingping Zhang, Gaoling Yang, Fei Li, Jianbing Shi, Haizheng Zhong
Direct in situ photolithography of perovskite quantum dots based on photocatalysis of lead bromide complexes
In: Nature Communications, vol. 13, no. 6713, 2022, (Perovskite nanomaterials may suffer degradation during conventional photolithography. Here, the authors report a non-destructive method for patterning perovskite quantum dots based on direct photopolymerization catalyzed by lead bromide complexes.).
Photolithography has shown great potential in patterning solution-processed nanomaterials for integration into advanced optoelectronic devices. However, photolithography of perovskite quantum dots (PQDs) has so far been hindered by the incompatibility of perovskite with traditional optical lithography processes where lots of solvents and high-energy ultraviolet (UV) light exposure are required. Herein, we report a direct in situ photolithography technique to pattern PQDs based on the photopolymerization catalyzed by lead bromide complexes. By combining direct photolithography with in situ fabrication of PQDs, this method allows to directly photolithograph perovskite precursors, avoiding the complicated lift-off processes and the destruction of PQDs by solvents or high-energy UV light, as PQDs are produced after lithography exposure. We further demonstrate that the thiol-ene free-radical photopolymerization is catalyzed by lead bromide complexes in the perovskite precursor solution, while no external initiators or catalysts are needed. Using direct in situ photolithography, PQD patterns with high resolution up to 2450 pixels per inch (PPI), excellent fluorescence uniformity, and good stability, are successfully demonstrated. This work opens an avenue for non-destructive direct photolithography of high-efficiency light-emitting PQDs, and potentially expands their application in various integrated optoelectronic devices.
Tolulope Michael Ajayi, Vijay Singh, Kyaw Zin Latt, Sanjoy Sarkar, Xinyue Cheng, Sineth Premarathna, Naveen K. Dandu, Shaoze Wang, Fahimeh Movahedifar, Sarah Wieghold, Nozomi Shirato, Volker Rose, Larry A. Curtiss, Anh T. Ngo, Eric Masson, Saw Wai Hla
Atomically precise control of rotational dynamics in charged rare-earth complexes on a metal surface
In: Nature Communications, vol. 13, no. 6305, 2022, (Rare-earth elements are vital to advanced technological applications ranging from spintronic devices to quantum information science. Here, the authors formed charged rare-earth complexes on a material surface and demonstrated atomically precise control on their rotational dynamics.).
Complexes containing rare-earth ions attract great attention for their technological applications ranging from spintronic devices to quantum information science. While charged rare-earth coordination complexes are ubiquitous in solution, they are challenging to form on materials surfaces that would allow investigations for potential solid-state applications. Here we report formation and atomically precise manipulation of rare-earth complexes on a gold surface. Although they are composed of multiple units held together by electrostatic interactions, the entire complex rotates as a single unit when electrical energy is supplied from a scanning tunneling microscope tip. Despite the hexagonal symmetry of the gold surface, a counterion at the side of the complex guides precise three-fold rotations and 100% control of their rotational directions is achieved using a negative electric field from the scanning probe tip. This work demonstrates that counterions can be used to control dynamics of rare-earth complexes on materials surfaces for quantum and nanomechanical applications.
Yuzhu Ma, Hongjin Zhang, Runfeng Lin, Yan Ai, Kun Lan, Linlin Duan, Wenyao Chen, Xuezhi Duan, Bing Ma, Changyao Wang, Xiaomin Li, Dongyuan Zhao
Remodeling nanodroplets into hierarchical mesoporous silica nanoreactors with multiple chambers
In: Nature Communications, vol. 13, no. 6136, 2022, (Multi-chambered structures have attracted great attention due to their ability to create multifunctional partitions in different chambers. Here, the authors prepared mesoporous silica nanoreactors with hierarchical chambers for catalytic cascades.).
Multi-chambered architectures have attracted much attention due to the ability to establish multifunctional partitions in different chambers, but manipulating the chamber numbers and coupling multi-functionality within the multi-chambered mesoporous nanoparticle remains a challenge. Herein, we propose a nanodroplet remodeling strategy for the synthesis of hierarchical multi-chambered mesoporous silica nanoparticles with tunable architectures. Typically, the dual-chambered nanoparticles with a high surface area of ~469 m2 g−1 present two interconnected cavities like a calabash. Furthermore, based on this nanodroplet remodeling strategy, multiple species (magnetic, catalytic, optic, etc.) can be separately anchored in different chamber without obvious mutual-crosstalk. We design a dual-chambered mesoporous nanoreactors with spatial isolation of Au and Pd active-sites for the cascade synthesis of 2-phenylindole from 1-nitro-2-(phenylethynyl)benzene. Due to the efficient mass transfer of reactants and intermediates in the dual-chambered structure, the selectivity of the target product reaches to ~76.5%, far exceeding that of single-chambered nanoreactors (~41.3%).
Yixuan Gao, Li Huang, Yun Cao, Marcus Richter, Jing Qi, Qi Zheng, Huan Yang, Ji Ma, Xiao Chang, Xiaoshuai Fu, Carlos-Andres Palma, Hongliang Lu, Yu-Yang Zhang, Zhihai Cheng, Xiao Lin, Min Ouyang, Xinliang Feng, Shixuan Du, Hong-Jun Gao
Selective activation of four quasi-equivalent C–H bonds yields N-doped graphene nanoribbons with partial corannulene motifs
In: Nature Communications, vol. 13, no. 6146, 2022, (Selective activation of C–H bonds is a key challenge in organic reactions. Here, the authors achieve the selective activation of four quasi-equivalent C–H bonds, leading to the formation of N-doped graphene nanoribbons with partial corannulene motifs.).
Selective C–H bond activation is one of the most challenging topics for organic reactions. The difficulties arise not only from the high C–H bond dissociation enthalpies but also the existence of multiple equivalent/quasi-equivalent reaction sites in organic molecules. Here, we successfully achieve the selective activation of four quasi-equivalent C–H bonds in a specially designed nitrogen-containing polycyclic hydrocarbon (N-PH). Density functional theory calculations reveal that the adsorption of N-PH on Ag(100) differentiates the activity of the four ortho C(sp3) atoms in the N-heterocycles into two groups, suggesting a selective dehydrogenation, which is demonstrated by sequential-annealing experiments of N-PH/Ag(100). Further annealing leads to the formation of N-doped graphene nanoribbons with partial corannulene motifs, realized by the C–H bond activation process. Our work provides a route of designing precursor molecules with ortho C(sp3) atom in an N-heterocycle to realize surface-induced selective dehydrogenation in quasi-equivalent sites.
Chong Li, Qi Liu, Shengyang Tao
Coemissive luminescent nanoparticles combining aggregation-induced emission and quenching dyes prepared in continuous flow
In: Nature Communications, vol. 13, no. 6034, 2022, (Developing efficient light harvesting systems at low cost is a challenge. Here, the authors synthesized coemissive dyes in a continuous flow microreactor featuring a controlled cascade FRET process combining aggregation-induced emission and quenching.).
Achieving an ideal light-harvesting system at a low cost remains a challenge. Herein, we report the synthesis of a hybrid dye system based on tetraphenylene (TPE) encapsulated organic dyes in a continuous flow microreactor. The composite dye nanoparticles (NPs) are synthesized based on supramolecular self-assembly to achieve the co-emission of aggregation-induced emission dyes and aggregation-caused quenching dyes (CEAA). Numerical simulations and molecular spectroscopy were used to investigate the synthesis mechanism of the CEAA dyes. Nanoparticles of CEAA dyes provide a platform for efficient cascade Förster resonance energy transfer (FRET). Composite dye nanoparticles of TPE and Nile red (NiR) are synthesized for an ideal light-harvesting system using coumarin 6 (C-6) as an energy intermediate. The light-harvesting system has a considerable red-shift distance (~126 nm), high energy-transfer efficiency (ΦET) of 99.37%, and an antenna effect of 26.23. Finally, the versatility of the preparation method and the diversity of CEAA dyes are demonstrated.
Jiří Doležal, Sofia Canola, Prokop Hapala, Rodrigo Cezar de Campos Ferreira, Pablo Merino, Martin Švec
Evidence of exciton-libron coupling in chirally adsorbed single molecules
In: Nature Communications, vol. 13, no. 6008, 2022, (Vibronic coupling in molecules plays an essential role in photophysics. Here, the authors observe optical fingerprints of the coupling between librational states and charged excited states in a single phthalocyanine molecule chirally absorbed on a surface.).
Interplay between motion of nuclei and excitations has an important role in molecular photophysics of natural and artificial structures. Here we provide a detailed analysis of coupling between quantized librational modes (librons) and charged excited states (trions) on single phthalocyanine dyes adsorbed on a surface. By means of tip-induced electroluminescence performed with a scanning probe microscope, we identify libronic signatures in spectra of chirally adsorbed phthalocyanines and find that these signatures are absent from spectra of symmetrically adsorbed species. We create a model of the libronic coupling based on the Franck-Condon principle to simulate the spectral features. Experimentally measured librational spectra match very well the theoretically calculated librational eigenenergies and peak intensities (Franck-Condon factors). Moreover, the comparison reveals an unexpected depopulation channel for the zero libron of the excited state that can be effectively controlled by tuning the size of the nanocavity. Our results showcase the possibility of characterizing the dynamics of molecules by their low-energy molecular modes using µeV-resolved tip-enhanced spectroscopy.
Arrigo Calzolari, Corey Oses, Cormac Toher, Marco Esters, Xiomara Campilongo, Sergei P. Stepanoff, Douglas E. Wolfe, Stefano Curtarolo
Plasmonic high-entropy carbides
In: Nature Communications, vol. 13, no. 5993, 2022, (Tunable plasmonic materials capable of surviving harsh environments are critical for advanced applications. Here, the authors report that some high-entropy transition-metal carbides can satisfy the requirements.).
Discovering multifunctional materials with tunable plasmonic properties, capable of surviving harsh environments is critical for advanced optical and telecommunication applications. We chose high-entropy transition-metal carbides because of their exceptional thermal, chemical stability, and mechanical properties. By integrating computational thermodynamic disorder modeling and time-dependent density functional theory characterization, we discovered a crossover energy in the infrared and visible range, corresponding to a metal-to-dielectric transition, exploitable for plasmonics. It was also found that the optical response of high-entropy carbides can be largely tuned from the near-IR to visible when changing the transition metal components and their concentration. By monitoring the electronic structures, we suggest rules for optimizing optical properties and designing tailored high-entropy ceramics. Experiments performed on the archetype carbide HfTa4C5 yielded plasmonic properties from room temperature to 1500K. Here we propose plasmonic transition-metal high-entropy carbides as a class of multifunctional materials. Their combination of plasmonic activity, high-hardness, and extraordinary thermal stability will result in yet unexplored applications.
Hyesung Jo, Dae Han Wi, Taegu Lee, Yongmin Kwon, Chaehwa Jeong, Juhyeok Lee, Hionsuck Baik, Alexander J. Pattison, Wolfgang Theis, Colin Ophus, Peter Ercius, Yea-Lee Lee, Seunghwa Ryu, Sang Woo Han, Yongsoo Yang
Direct strain correlations at the single-atom level in three-dimensional core-shell interface structures
In: Nature Communications, vol. 13, no. 5957, 2022, (Understanding 3D interfacial strain at the atomic level has been a long-sought challenge in the field of core-shell nanomaterials. Here, the authors address this challenge by revealing the full 3D atomic structures of Pd@Pt core-shell nanoparticles.).
Nanomaterials with core-shell architectures are prominent examples of strain-engineered materials. The lattice mismatch between the core and shell materials can cause strong interface strain, which affects the surface structures. Therefore, surface functional properties such as catalytic activities can be designed by fine-tuning the misfit strain at the interface. To precisely control the core-shell effect, it is essential to understand how the surface and interface strains are related at the atomic scale. Here, we elucidate the surface-interface strain relations by determining the full 3D atomic structure of Pd@Pt core-shell nanoparticles at the single-atom level via atomic electron tomography. Full 3D displacement fields and strain profiles of core-shell nanoparticles were obtained, which revealed a direct correlation between the surface and interface strain. The strain distributions show a strong shape-dependent anisotropy, whose nature was further corroborated by molecular statics simulations. From the observed surface strains, the surface oxygen reduction reaction activities were predicted. These findings give a deep understanding of structure-property relationships in strain-engineerable core-shell systems, which can lead to direct control over the resulting catalytic properties.
Nan Xia, Jianpei Xing, Di Peng, Shiyu Ji, Jun Zha, Nan Yan, Yan Su, Xue Jiang, Zhi Zeng, Jijun Zhao, Zhikun Wu
Assembly-induced spin transfer and distance-dependent spin coupling in atomically precise AgCu nanoclusters
In: Nature Communications, vol. 13, no. 5934, 2022, (The assembly of atomically precise clusters into ordered superstructures enables new functional material designs. Here, the authors propose a strategy for linear arrangements of AgCu clusters and explore the consequent transfer and coupling of magnetic spins.).
Nanoparticle assembly paves the way for unanticipated properties and applications from the nanoscale to the macroscopic world. However, the study of such material systems is greatly inhibited due to the obscure compositions and structures of nanoparticles (especially the surface structures). The assembly of atomically precise nanoparticles is challenging, and such an assembly of nanoparticles with metal core sizes strictly larger than 1 nm has not been achieved yet. Here, we introduced an on-site synthesis-and-assembly strategy, and successfully obtained a straight-chain assembly structure consisting of Ag77Cu22(CHT)48 (CHT: cyclohexanethiolate) nanoparticles with two nanoparticles separated by one S atom, as revealed by mass spectrometry and single crystal X-ray crystallography. Although Ag77Cu22(CHT)48 bears one unpaired shell-closing electron, the magnetic moment is found to be mainly localized at the S linker with magnetic isotropy, and the sulfur radicals were experimentally verified and found to be unstable after disassembly, demonstrating assembly-induced spin transfer. Besides, spin nanoparticles are found to couple and lose their paramagnetism at sufficiently short inter-nanoparticle distance, namely, the spin coupling depends on the inter-nanoparticle distance. However, it is not found that the spin coupling leads to the nanoparticle growth.
Zhiwei Yang, Yanze Wei, Jingjing Wei, Zhijie Yang
Chiral superstructures of inorganic nanorods by macroscopic mechanical grinding
In: Nature Communications, vol. 13, no. 5844, 2022, (Chiroptic materials made of self-assembled nanomaterials are essential for advanced optical applications. Here, the authors show that macroscopic grinding can break the symmetry in achiral superlattices of inorganic nanorods, generating chiral superstructures.).
The development of mechanochemistry substantially expands the traditional synthetic realm at the molecular level. Here, we extend the concept of mechanochemistry from atomic/molecular solids to the nanoparticle solids, and show how the macroscopic grinding is being capable of generating chirality in self-assembled nanorod (NR) assemblies. Specifically, the weak van der Waals interaction is dominated in self-assembled NR assemblies when their surface is coated with aliphatic chains, which can be overwhelmed by a press-and-rotate mechanic force macroscopically. The chiral sign of the NR assemblies can be well-controlled by the rotating directions, where the clockwise and counter-clockwise rotation leads to the positive and negative Cotton effect in circular dichroism and circularly polarized luminescence spectra, respectively. Importantly, we show that the present approach can be applied to NRs of diverse inorganic materials, including CdSe, CdSe/CdS, and TiO2. Equally important, the as-prepared chiral NR assemblies could be served as porous yet robust chiral substrates, which enable to host other molecular materials and induce the chirality transfer from substrate to the molecular system.
Zhen-Yu Yi, Xue-Qing Yang, Jun-Jie Duan, Xiong Zhou, Ting Chen, Dong Wang, Li-Jun Wan
Evolution of Br⋯Br contacts in enantioselective molecular recognition during chiral 2D crystallization
In: Nature Communications, vol. 13, no. 5850, 2022, (Halogen-mediated interactions control molecular recognition in many chemical and biological systems. Here, the authors demonstrate two types of Br⋯Br contacts and their importance in chiral on-surface crystallization.).
Halogen-mediated interactions play an important role in molecular recognition and crystallization in many chemical and biological systems, whereas their effect on homochiral versus heterochiral recognition and crystallization has rarely been explored. Here we demonstrate the evolution of Br⋯Br contacts in chiral recognition during 2D crystallization. On Ag(100), type I contacts prevail at low coverage and lead to homochiral recognition and the formation of 2D conglomerates; whereas type II contacts mediating heterochiral recognition are suppressed at medium coverage and appear in the racemates induced by structural transitions at high coverage. On Ag(111), type I contacts dominate the 2D crystallization and generate 2D conglomerates exclusively. DFT calculations suggest that the energy difference between type I and type II contacts is reversed upon adsorption due to the substrate induced mismatch energy penalty. This result provides fundamental understanding of halogen-mediated interactions in molecular recognition and crystallization on surface.
Maryam Arabi, Abbas Ostovan, Yunqing Wang, Rongchao Mei, Longwen Fu, Jinhua Li, Xiaoyan Wang, Lingxin Chen
Chiral molecular imprinting-based SERS detection strategy for absolute enantiomeric discrimination
In: Nature Communications, vol. 13, no. 5757, 2022, (Absolute chiral discrimination in chiral imprinted systems is complicated by the nonspecific binding of enantiomers. Here, the authors report a SERS “inspector” recognition mechanism to distinguish between specifically and nonspecifically bound enantiomers, even in seawater and urine.).
Chiral discrimination is critical in environmental and life sciences. However, an ideal chiral discrimination strategy has not yet been developed because of the inevitable nonspecific binding entity of wrong enantiomers or insufficient intrinsic optical activities of chiral molecules. Here, we propose an “inspector” recognition mechanism (IRM), which is implemented on a chiral imprinted polydopamine (PDA) layer coated on surface-enhanced Raman scattering (SERS) tag layer. The IRM works based on the permeability change of the imprinted PDA after the chiral recognition and scrutiny of the permeability by an inspector molecule. Good enantiomer can specifically recognize and fully fill the chiral imprinted cavities, whereas the wrong cannot. Then a linear shape aminothiol molecule, as an inspector of the recognition status is introduced, which can only percolate through the vacant and nonspecifically occupied cavities, inducing the SERS signal to decrease. Accordingly, chirality information exclusively stems from good enantiomer specific binding, while nonspecific recognition of wrong enantiomer is curbed. The IRM benefits from sensitivity and versatility, enabling absolute discrimination of a wide variety of chiral molecules regardless of size, functional groups, polarities, optical activities, Raman scattering, and the number of chiral centers.
Lei Lei, Yubin Wang, Weixin Xu, Renguang Ye, Youjie Hua, Degang Deng, Liang Chen, Paras N. Prasad, Shiqing Xu
Manipulation of time-dependent multicolour evolution of X-ray excited afterglow in lanthanide-doped fluoride nanoparticles
In: Nature Communications, vol. 13, no. 5739, 2022, (X-ray activated afterglow nanomaterials are desirable components for advanced optoelectronic applications. Here, the authors present pathways to modulate the stimulus-responsive color emissions in lanthanide-doped fluoride core-shell nanoparticles.).
External manipulation of emission colour is of significance for scientific research and applications, however, the general stimulus-responsive colour modulation method requires both stringent control of microstructures and continously adjustment of particular stimuli conditions. Here, we introduce pathways to manipulate the kinetics of time evolution of both intensity and spectral characteristics of X-ray excited afterglow (XEA) by regioselective doping of lanthanide activators in core-shell nanostructures. Our work reported here reveals the following phenomena: 1. The XEA intensities of multiple lanthanide activators are significantly enhanced via incorporating interstitial Na+ ions inside the nanocrystal structure. 2. The XEA intensities of activators exhibit diverse decay rates in the core and the shell and can largely be tuned separately, which enables us to realize a series of core@shell NPs featuring distinct time-dependent afterglow colour evolution. 3. A core/multi-shell NP structure can be designed to simultaneously generate afterglow, upconversion and downshifting to realize multimode time-dependent multicolour evolutions. These findings can promote the development of superior XEA and plentiful spectral manipulation, opening up a broad range of applications ranging from multiplexed biosensing, to high-capacity information encryption, to multidimensional displays and to multifunctional optoelectronic devices.
Jing Ai, Xueliang Zhang, Te Bai, Qing Shen, Peter Oleynikov, Yingying Duan, Osamu Terasaki, Shunai Che, Lu Han
Synchronous quantitative analysis of chiral mesostructured inorganic crystals by 3D electron diffraction tomography
In: Nature Communications, vol. 13, no. 5718, 2022, (Chiral mesostructured inorganic crystals exhibit distinctive twisting and helical hierarchical stacking. Here, the authors report a general approach for the synchronous quantitative analysis of rotation axis, torsion angle, pitch length, and arrangement modes.).
Chiral mesostructures exhibit distinctive twisting and helical hierarchical stacking ranging from atomic to micrometre scales with fascinating structural-chiral anisotropy properties. However, the detailed determination of their multilevel chirality remains challenging due to the limited information from spectroscopy, diffraction techniques, scanning electron microscopy and the two-dimensional projections in transmission electron microscopy. Herein, we report a general approach to determine chiral hierarchical mesostructures based on three-dimensional electron diffraction tomography (3D EDT), by which the structure can be solved synchronously according to the quantitative measurement of diffraction spot deformations and their arrangement in reciprocal space. This method was verified on two samples—chiral mesostructured nickel molybdate and chiral mesostructured tin dioxide—revealing hierarchical chiral structures that cannot be determined by conventional techniques. This approach provides more precise and comprehensive identification of the hierarchical mesostructures, which is expected to advance our understanding of structural–chiral anisotropy at the fundamental level.
Corentin Dabard, Victor Guilloux, Charlie Gréboval, Hong Po, Lina Makke, Ningyuan Fu, Xiang Zhen Xu, Mathieu G. Silly, Gilles Patriarche, Emmanuel Lhuillier, Thierry Barisien, Juan I. Climente, Benjamin T. Diroll, Sandrine Ithurria
Double-crowned 2D semiconductor nanoplatelets with bicolor power-tunable emission
In: Nature Communications, vol. 13, no. 5094, 2022, (Nanocrystals are desirable light sources for advanced display technologies. Here, the authors report on double-crowned 2D semiconductor nanoplatelets as light downconverters that offer both green and red emissions to achieve a wide color gamut.).
Nanocrystals (NCs) are now established building blocks for optoelectronics and their use as down converters for large gamut displays has been their first mass market. NC integration relies on a combination of green and red NCs into a blend, which rises post-growth formulation issues. A careful engineering of the NCs may enable dual emissions from a single NC population which violates Kasha’s rule, which stipulates that emission should occur at the band edge. Thus, in addition to an attentive control of band alignment to obtain green and red signals, non-radiative decay paths also have to be carefully slowed down to enable emission away from the ground state. Here, we demonstrate that core/crown/crown 2D nanoplatelets (NPLs), made of CdSe/CdTe/CdSe, can combine a large volume and a type-II band alignment enabling simultaneously red and narrow green emissions. Moreover, we demonstrate that the ratio of the two emissions can be tuned by the incident power, which results in a saturation of the red emission due to non-radiative Auger recombination that affects this emission much stronger than the green one. Finally, we also show that dual-color, power tunable, emission can be obtained through an electrical excitation.
Lukas Grote, Martin Seyrich, Ralph Döhrmann, Sani Harouna-Mayer, Federica Mancini, Emilis Kaziukenas, Irene Fernandez-Cuesta, Cecilia Zito, Olga Vasylieva, Felix Wittwer, Michal Odstrcil, Natnael Mogos, Mirko Landmann, Christian Schroer, Dorota Koziej
Imaging Cu2O nanocube hollowing in solution by quantitative in-situ X-ray ptychography
In: Nature Communications, vol. 13, no. 4971, 2022, (Observing morphological changes of nanoparticles in solution requires advanced in-situ imaging methods. Here, the authors use X-ray ptychography to image the growth and hollowing of Cu2O nanocubes in 3D.).
Understanding morphological changes of nanoparticles in solution is essential to tailor the functionality of devices used in energy generation and storage. However, we lack experimental methods that can visualize these processes in solution, or in electrolyte, and provide three-dimensional information. Here, we show how X-ray ptychography enables in situ nano-imaging of the formation and hollowing of nanoparticles in solution at 155°C. We simultaneously image the growth of about 100 nanocubes with a spatial resolution of 66 nm. The quantitative phase images give access to the third dimension, allowing to additionally study particle thickness. We reveal that the substrate hinders their out-of-plane growth, thus the nanocubes are in fact nanocuboids. Moreover, we observe that the reduction of Cu2O to Cu triggers the hollowing of the nanocuboids. We critically assess the interaction of X-rays with the liquid sample. Our method enables detailed in-solution imaging for a wide range of reaction conditions.
Hajir Hilal, Qiang Zhao, Jeongwon Kim, Sungwoo Lee, MohammadNavid Haddadnezhad, Sungjae Yoo, Soohyun Lee, Woongkyu Park, Woocheol Park, Jaewon Lee, Joong Wook Lee, Insub Jung, Sungho Park
Three-dimensional nanoframes with dual rims as nanoprobes for biosensing
In: Nature Communications, vol. 13, no. 4813, 2022, ( Most SERS-active nanostructures suffer from low robustness against misalignment to field polarization. Here, the authors demonstrate three-dimensional nanoframes of octahedral geometry, with two rims engraved on each facet, as polarization-independent SERS nanoprobes.).
Three-dimensional (3D) nanoframe structures are very appealing because their inner voids and ridges interact efficiently with light and analytes, allowing for effective optical-based sensing. However, the realization of complex nanoframe architecture with high yield is challenging because the systematic design of such a complicated nanostructure lacks an appropriate synthesis protocol. Here, we show the synthesis method for complex 3D nanoframes wherein two-dimensional (2D) dual-rim nanostructures are engraved on each facet of octahedral nanoframes. The synthetic scheme proceeds through multiple executable on-demand steps. With Au octahedral nanoparticles as a sacrificial template, sequential processes of edge-selective Pt deposition and inner Au etching lead to Pt octahedral mono-rim nanoframes. Then, adlayers of Au are grown on Pt skeletons via the Frank-van der Merwe mode, forming sharp and well-developed edges. Next, Pt selective deposition on both the inner and outer boundaries leads to tunable geometric patterning on Au. Finally, after the selective etching of Au, Pt octahedral dual-rim nanoframes with highly homogeneous size and shape are achieved. In order to endow plasmonic features, Au is coated around Pt frames while retaining their geometric shape. The resultant plasmonic dual-rim engraved nanoframes possess strong light entrapping capability verified by single-particle surface-enhanced Raman scattering (SERS) and show the potential of nanoprobes for biosensing through SERS-based immunoassay.
Lei Zhang, Chen Yang, Chenxi Lu, Xingxing Li, Yilin Guo, Jianning Zhang, Jinglong Lin, Zhizhou Li, Chuancheng Jia, Jinlong Yang, K. N. Houk, Fanyang Mo, Xuefeng Guo
Precise electrical gating of the single-molecule Mizoroki-Heck reaction
In: Nature Communications, vol. 13, no. 4552 , 2022, (Guiding chemical reactions in a predictable and controllable manner is an ultimate goal of chemistry. Here, the authors show tuning of the single-molecule Mizoroki-Heck catalytic cycle through electrical gating and direct in-situ detection.).
Precise tuning of chemical reactions with predictable and controllable manners, an ultimate goal chemists desire to achieve, is valuable in the scientific community. This tunability is necessary to understand and regulate chemical transformations at both macroscopic and single-molecule levels to meet demands in potential application scenarios. Herein, we realise accurate tuning of a single-molecule Mizoroki-Heck reaction via applying gate voltages as well as complete deciphering of its detailed intrinsic mechanism by employing an in-situ electrical single-molecule detection, which possesses the capability of single-event tracking. The Mizoroki-Heck reaction can be regulated in different dimensions with a constant catalyst molecule, including the molecular orbital gating of Pd(0) catalyst, the on/off switching of the Mizoroki-Heck reaction, the promotion of its turnover frequency, and the regulation of each elementary reaction within the Mizoroki-Heck catalytic cycle. These results extend the tuning scope of chemical reactions from the macroscopic view to the single-molecule approach, inspiring new insights into designing different strategies or devices to unveil reaction mechanisms and discover novel phenomena.
Sungjae Yoo, Jaewon Lee, Hajir Hilal, Insub Jung, Woongkyu Park, Joong Wook Lee, Soobong Choi, Sungho Park
Nesting of multiple polyhedral plasmonic nanoframes into a single entity
In: Nature Communications, vol. 13, no. 4544 , 2022, (The spatial configuration of nanostructure building blocks determines the physical and optical properties of their superstructures. Here, the authors report on complex nanoparticles in which different geometric forms of nanoframes are nested into a single entity by multistep chemical reactions.).
The development of plasmonic nanostructures with intricate nanoframe morphologies has attracted considerable interest for improving catalytic and optical properties. However, arranging multiple nanoframes in one nanostructure especially, in a solution phase remains a great challenge. Herein, we show complex nanoparticles by embedding various shapes of three-dimensional polyhedral nanoframes within a single entity through rationally designed synthetic pathways. This synthetic strategy is based on the selective deposition of platinum atoms on high surface energy facets and subsequent growth into solid platonic nanoparticles, followed by the etching of inner Au domains, leaving complex nanoframes. Our synthetic routes are rationally designed and executable on-demand with a high structural controllability. Diverse Au solid nanostructures (octahedra, truncated octahedra, cuboctahedra, and cubes) evolved into complex multi-layered nanoframes with different numbers/shapes/sizes of internal nanoframes. After coating the surface of the nanoframes with plasmonically active metal (like Ag), the materials exhibited highly enhanced electromagnetic near-field focusing embedded within the internal complicated rim architecture.
Mingu Kang, Hyun Woo Kim, Elham Oleiki, Yeonjeong Koo, Hyeongwoo Lee, Huitae Joo, Jinseong Choi, Taeyong Eom, Geunsik Lee, Yung Doug Suh, Kyoung-Duck Park
Conformational heterogeneity of molecules physisorbed on a gold surface at room temperature
In: Nature Communications, vol. 13, no. 4133, 2022, (Tip-enhanced vibrational spectroscopy at room temperature is complicated by molecular conformational dynamics, photobleaching, contaminations, and chemical reactions in air. This study demonstrates that a sub-nm protective layer of Al2O3 provides robust conditions for probing single-molecule conformations.).
A quantitative single-molecule tip-enhanced Raman spectroscopy (TERS) study at room temperature remained a challenge due to the rapid structural dynamics of molecules exposed to air. Here, we demonstrate the hyperspectral TERS imaging of single or a few brilliant cresyl blue (BCB) molecules at room temperature, along with quantitative spectral analyses. Robust chemical imaging is enabled by the freeze-frame approach using a thin Al2O3 capping layer, which suppresses spectral diffusions and inhibits chemical reactions and contamination in air. For the molecules resolved spatially in the TERS image, a clear Raman peak variation up to 7.5 cm−1 is observed, which cannot be found in molecular ensembles. From density functional theory-based quantitative analyses of the varied TERS peaks, we reveal the conformational heterogeneity at the single-molecule level. This work provides a facile way to investigate the single-molecule properties in interacting media, expanding the scope of single-molecule vibrational spectroscopy studies.
Nam Heon Cho, Young Bi Kim, Yoon Young Lee, Sang Won Im, Ryeong Myeong Kim, Jeong Won Kim, Seok Daniel Namgung, Hye-Eun Lee, Hyeohn Kim, Jeong Hyun Han, Hye Won Chung, Yoon Ho Lee, Jeong Woo Han, Ki Tae Nam
Adenine oligomer directed synthesis of chiral gold nanoparticles
In: Nature Communications, vol. 13, no. 3831, 2022, (Chiral plasmonic nanoparticles are of great interest in nanotechnology. Here, the authors demonstrate chiral shape guidance by single-stranded oligonucleotides during particle growth based on sequence-specific hydrogen bonding within the strand.).
Precise control of morphology and optical response of 3-dimensional chiral nanoparticles remain as a significant challenge. This work demonstrates chiral gold nanoparticle synthesis using single-stranded oligonucleotide as a chiral shape modifier. The homo-oligonucleotide composed of Adenine nucleobase specifically show a distinct chirality development with a dissymmetric factor up to g ~ 0.04 at visible wavelength, whereas other nucleobases show no development of chirality. The synthesized nanoparticle shows a counter-clockwise rotation of generated chiral arms with approximately 200 nm edge length. The molecular dynamics and density functional theory simulations reveal that Adenine shows the highest enantioselective interaction with Au(321)R/S facet in terms of binding orientation and affinity. This is attributed to the formation of sequence-specific intra-strand hydrogen bonding between nucleobases. We also found that different sequence programming of Adenine-and Cytosine-based oligomers result in chiral gold nanoparticles’ morphological and optical change. These results extend our understanding of the biomolecule-directed synthesis of chiral gold nanoparticles to sequence programmable deoxyribonucleic acid and provides a foundation for programmable synthesis of chiral gold nanoparticles.
Li-Zhe Feng, Jing-Jing Wang, Tao Ma, Yi-Chen Yin, Kuang-Hui Song, Zi-Du Li, Man-Man Zhou, Shan Jin, Taotao Zhuang, Fengjia Fan, Manzhou Zhu, Hong-Bin Yao
Biomimetic non-classical crystallization drives hierarchical structuring of efficient circularly polarized phosphors
In: Nature Communications, vol. 13, no. 3339, 2022, (Chiral emitters with high photoluminescence quantum yield are desirable for use in circularly polarized LEDs. The authors demonstrate the transfer of chirality from nanoscale copper iodide clusters to microscale chiral luminescent polycrystals by non-classical crystallization.).
Hierarchically structured chiral luminescent materials hold promise for achieving efficient circularly polarized luminescence. However, a feasible chemical route to fabricate hierarchically structured chiral luminescent polycrystals is still elusive because of their complex structures and complicated formation process. We here report a biomimetic non-classical crystallization (BNCC) strategy for preparing efficient hierarchically structured chiral luminescent polycrystals using well-designed highly luminescent homochiral copper(I)-iodide hybrid clusters as basic units for non-classical crystallization. By monitoring the crystallization process, we unravel the BNCC mechanism, which involves crystal nucleation, nanoparticles aggregation, oriented attachment, and mesoscopic transformation processes. We finally obtain the circularly polarized phosphors with both high luminescent efficiency of 32% and high luminescent dissymmetry factor of 1.5 × 10^−2, achieving the demonstration of a circularly polarized phosphor converted light emitting diode with a polarization degree of 1.84% at room temperature. Our designed BNCC strategy provides a simple, reliable, and large-scale synthetic route for preparing bright circularly polarized phosphors.