Nanoscale Horizons最新文献

{"title":"Insight into mechanism for remarkable photocatalytic hydrogen evolution of Cu/Pr dual atom co-modified TiO2†","authors":"Hongshun Zheng, Baoye Zi, Tong Zhou, Guoyang Qiu, Zhongge Luo, Qingjie Lu, Alain Rafael Puente Santiago, Yumin Zhang, Jianhong Zhao, Jin Zhang, Tianwei He and Qingju Liu","doi":"10.1039/D4NH00196F","DOIUrl":"10.1039/D4NH00196F","url":null,"abstract":"<p >The development of high-activity photocatalysts is crucial for the current large-scale development of photocatalytic hydrogen applications. Herein, we have developed a strategy to significantly enhance the hydrogen photocatalytic activity of Cu/Pr di-atom co-modified TiO<small>₂</small> architectures by selectively anchoring Cu single atoms on the oxygen vacancies of the TiO<small>₂</small> surface and replacing a trace of Ti atoms in the bulk with rare earth Pr atoms. Calculation results demonstrated that the synergistic effect between Cu single atoms and Pr atoms regulates the electronic structure of Cu/Pr–TiO<small>₂</small>, thus promoting the separation of photogenerated carriers and their directional migration to Cu single atoms for the photocatalytic reaction. Furthermore, the d-band center of Cu/Pr–TiO<small>₂</small>, which is located at −4.70 eV, optimizes the adsorption and desorption behavior of H*. Compared to TiO<small>₂</small>, Pr–TiO<small>₂</small>, and Cu/TiO<small>₂</small>, Cu/Pr–TiO<small>₂</small> displays the best H* adsorption Gibbs free energy (−0.047 eV). Furthermore, experimental results confirmed that the photogenerated carrier lifetime of Cu/Pr–TiO<small>₂</small> is not only the longest (2.45 ns), but its hydrogen production rate (34.90 mmol g<small>⁻¹</small> h<small>⁻¹</small>) also significantly surpasses those of Cu/TiO<small>₂</small> (13.39 mmol g<small>⁻¹</small> h<small>⁻¹</small>) and Pr–TiO<small>₂</small> (0.89 mmol g<small>⁻¹</small> h<small>⁻¹</small>). These findings open up a novel atomic perspective for the development of optimal hydrogen activity in dual-atom-modified TiO<small>₂</small> photocatalysts.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141553646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical regulation to interfacial thermal transport in GaN/diamond heterostructures for thermal switch†","authors":"Xiaotong Yu, Yifan Li, Renjie He, Yanwei Wen, Rong Chen, Baoxing Xu and Yuan Gao","doi":"10.1039/D4NH00245H","DOIUrl":"10.1039/D4NH00245H","url":null,"abstract":"<p >Gallium nitride offers an ideal material platform for next-generation high-power electronics devices, which enable a spectrum of applications. The thermal management of the ever-growing power density has become a major bottleneck in the performance, reliability, and lifetime of the devices. GaN/diamond heterostructures are usually adopted to facilitate heat dissipation, given the extraordinary thermal conduction properties of diamonds. However, thermal transport is limited by the interfacial conductance at the material interface between GaN and diamond, which is associated with significant mechanical stress at the atomic level. In this work, we investigate the effect of mechanical strain perpendicular to the GaN/diamond interface on the interfacial thermal conductance of heterostructures using full-atom non-equilibrium molecular dynamics simulations. We found that the heterostructure exhibits severe mechanical stress at the interface in the absence of loading, which is due to lattice mismatch. Upon tensile/compressive loading, the interfacial stress is more pronounced, and the strain is not identical across the interface owing to the contrasting elastic moduli of GaN and diamond. In addition, the interfacial thermal conductance can be notably enhanced and suppressed by tensile and compressive strains, respectively, leading to a 400% variation in thermal conductance. More detailed analyses reveal that the change in interfacial thermal conductance is related to the surface roughness and interfacial bonding strength, as described by a generalized relationship. Moreover, phonon analyses suggest that the unequal mechanical deformation under compressive strain in GaN and diamond induces different frequency shifts in the phonon spectra, leading to an enhancement in phonon overlapping energy, which promotes phonon transport at the interface and elevates the thermal conductance and <em>vice versa</em> for tensile strain. The effect of strain on interface thermal conductance was investigated at various temperatures. Based on the mechanical tunability of thermal conductance, we propose a conceptual design for a mechanical thermal switch that regulates thermal conductance with excellent sensitivity and high responsiveness. This study offers a fundamental understanding of how mechanical strain can adjust interface thermal conductance in GaN/diamond heterostructures with respect to mechanical stress, deformation, and phonon properties. These results and findings lay the theoretical foundation for designing thermal management devices in a strain environment and shed light on developing intelligent thermal devices by leveraging the interplay between mechanics and thermal transport.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141571819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Colloidal TiO2 nanocrystals with engineered defectivity and optical properties†","authors":"Julia J. Chang, Bin Yuan, Sandro Mignuzzi, Riccardo Sapienza, Francesco Mezzadri and Ludovico Cademartiri","doi":"10.1039/D4NH00143E","DOIUrl":"10.1039/D4NH00143E","url":null,"abstract":"<p >Partially reduced forms of titanium dioxide (sometimes called “black” titania) have attracted widespread interest as promising photocatalysts of oxidation due to their absorption in the visible region. The main approaches to produce it rely on postprocessing at high temperatures (up to 800 °C) and high pressures (up to 40 bar) or on highly reactive precursors (<em>e.g.</em>, TiH<small>₂</small>), and yield powders with poorly controlled sizes, shapes, defect concentrations and distributions. We describe an approach for the one-step synthesis of TiO<small>₂</small> colloidal nanocrystals at atmospheric pressure and temperatures as low as 280 °C. The temperature of the reaction allows the density of oxygen vacancies to be controlled by nearly two orders of magnitude independently of their size, shape, or colloidal stability. This synthetic pathway appears to produce vacancies that are homogeneously distributed in the nanocrystals, rather than being concentrated in an amorphous shell. As a result, the defects are protected from oxidation and result in stable optical properties in oxidizing environments.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Outstanding Reviewers for <i>Nanoscale Horizons</i> in 2023.","authors":"","doi":"10.1039/d4nh90049a","DOIUrl":"https://doi.org/10.1039/d4nh90049a","url":null,"abstract":"<p><p>We would like to take this opportunity to thank all of <i>Nanoscale Horizons</i>' reviewers for helping to preserve quality and integrity in the nanoscience literature. We would also like to highlight the Outstanding Reviewers for <i>Nanoscale Horizons</i> in 2023.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Outstanding Reviewers for Nanoscale Horizons in 2023","authors":"","doi":"10.1039/D4NH90049A","DOIUrl":"10.1039/D4NH90049A","url":null,"abstract":"<p >We would like to take this opportunity to thank all of <em>Nanoscale Horizons</em>’ reviewers for helping to preserve quality and integrity in the nanoscience literature. We would also like to highlight the Outstanding Reviewers for <em>Nanoscale Horizons</em> in 2023.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142003053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancements in molecular disassembly of optical probes: a paradigm shift in sensing, bioimaging, and therapeutics","authors":"Karolina Saczuk, Marta Dudek, Katarzyna Matczyszyn and Marco Deiana","doi":"10.1039/D4NH00186A","DOIUrl":"10.1039/D4NH00186A","url":null,"abstract":"<p >The majority of self-assembled fluorescent dyes suffer from aggregation-caused quenching (ACQ), which detrimentally affects their diagnostic and therapeutic effectiveness. While aggregation-induced emission (AIE) active dyes offer a promising solution to overcome this limitation, they may face significant challenges as the intracellular environment often prevents aggregation, leading to disassembly and posing challenges for AIE fluorogens. Recent progress in signal amplification through the disassembly of ACQ dyes has opened new avenues for creating ultrasensitive optical sensors and enhancing phototherapeutic outcomes. These advances are well-aligned with cutting-edge technologies such as single-molecule microscopy and targeted molecular therapies. This work explores the concept of disaggregation-induced emission (DIE), showcasing the revolutionary capabilities of DIE-based dyes from their design to their application in sensing, bioimaging, disease monitoring, and treatment in both cellular and animal models. Our objective is to provide an in-depth comparison of aggregation <em>versus</em> disaggregation mechanisms, aiming to stimulate further advancements in the design and utilization of ACQ fluorescent dyes through DIE technology. This initiative is poised to catalyze scientific progress across a broad spectrum of disciplines.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/nh/d4nh00186a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Art etching of graphene","authors":"Gayathri Devi N, The-Hung Mai, Ram K. Gupta and Phuong V. Pham","doi":"10.1039/D4NH00077C","DOIUrl":"10.1039/D4NH00077C","url":null,"abstract":"<p >The growth of graphene on a metal substrate using chemical vapor deposition (CVD), assisted by hydrocarbons such as CH<small>₄</small>, C<small>₃</small>H<small>₈</small>, C<small>₂</small>H<small>₆</small>, <em>etc.</em> leads to the formation of carbon clusters, amorphous carbon, or any other structure. These carbon species are considered as unwanted impurities; thus a conventional etching step is used simultaneously with CVD graphene growth to remove them using an etching agent. Meanwhile, art etching is a specific method of producing controlled non-Euclidean and Euclidean geometries by employing intricate and precise etching parameters or integrated growth/etching modes. Agents such as H<small>₂</small>, O<small>₂</small>, CH<small>₄</small>, Ar, and others are applied as art etching agents to support the art etching technology. This technique can generate nanopores and customize the properties of graphene, facilitating specific applications such as nanodevices, nanosensors, nanofilters, <em>etc.</em> This comprehensive review investigates how precursor gases concurrently induce graphene growth and art etching during a chemical vapor deposition process, resulting in beautifully etched patterns. Furthermore, it discusses the techniques leading to the creation of these patterns. Finally, the challenges, uses, and perspectives of these non-Euclidean and Euclidean-shaped art etched graphene geometries are discussed.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141490069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bimodal alteration of cognitive accuracy for spintronic artificial neural networks","authors":"Anuj Kumar, Debasis Das, Dennis J. X. Lin, Lisen Huang, Sherry L. K. Yap, Hang Khume Tan, Royston J. J. Lim, Hui Ru Tan, Yeow Teck Toh, Sze Ter Lim, Xuanyao Fong and Pin Ho","doi":"10.1039/D4NH00097H","DOIUrl":"10.1039/D4NH00097H","url":null,"abstract":"<p >Spintronics-based artificial neural networks (ANNs) exhibiting nonvolatile, fast, and energy-efficient computing capabilities are promising neuromorphic hardware for performing complex cognitive tasks of artificial intelligence and machine learning. Early experimental efforts focused on multistate device concepts to enhance synaptic weight precisions, albeit compromising on cognitive accuracy due to their low magnetoresistance. Here, we propose a hybrid approach based on the tuning of tunnel magnetoresistance (TMR) and the number of states in the compound magnetic tunnel junctions (MTJs) to improve the cognitive performance of an all-spin ANN. A TMR variation of 33–78% is controlled by the free layer (FL) thickness wedge (1.6–2.6 nm) across the wafer. Meanwhile, the number of resistance states in the compound MTJ is manipulated by varying the number of constituent MTJ cells (<em>n</em> = 1–3), generating <em>n</em> + 1 states with a TMR difference between consecutive states of at least 21%. Using MNIST handwritten digit and fashion object databases, the test accuracy of the compound MTJ ANN is observed to increase with the number of intermediate states for a fixed FL thickness or TMR. Meanwhile, the test accuracy for a 1-cell MTJ increases linearly by 8.3% and 7.4% for handwritten digits and fashion objects, respectively, with increasing TMR. Interestingly, a multifarious TMR dependence of test accuracy is observed with the increasing synaptic complexity in the 2- and 3-cell MTJs. By leveraging on the bimodal tuning of multilevel and TMR, we establish viable paths for enhancing the cognitive performance of spintronic ANN for in-memory and neuromorphic computing.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/nh/d4nh00097h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141490070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent progress in atomically precise metal nanoclusters for photocatalytic application","authors":"Yuanxin Du, Chengqi Li, Yali Dai, Haijiao Yin and Manzhou Zhu","doi":"10.1039/D4NH00197D","DOIUrl":"10.1039/D4NH00197D","url":null,"abstract":"<p >Photocatalysis is a widely recognized green and sustainable technology that can harness inexhaustible solar energy to carry out chemical reactions, offering the opportunity to mitigate environmental issues and the energy crisis. Photocatalysts with wide spectral response and rapid charge transfer capability are crucial for highly efficient photocatalytic activity. Atomically precise metal nanoclusters (NCs), an emerging atomic-level material, have attracted great interests owing to their ultrasmall size, unique atomic stacking, abundant surface active sites, and quantum confinement effect. In particular, the molecule-like discrete electronic energy level endows them with small-band-gap semiconductor behavior, which allows for photoexcitation in order to generate electrons and holes to participate in the photoredox reaction. In addition, metal NCs exhibit strong light-harvesting ability in the wide spectral UV–near IR region, and the diversity of optical absorption properties can be precisely regulated by the composition and structure. These merits make metal NCs ideal candidates for photocatalysis. In this review, the recent advances in atomically-precise metal NCs for photocatalytic application are summarized, including photocatalytic water splitting, CO<small>₂</small> reduction, organic transformation, photoelectrocatalytic reactions, N<small>₂</small> fixation and H<small>₂</small>O<small>₂</small> production. In addition, the strategy for promoting photostability, charge transfer and separation efficiency of metal NCs is highlighted. Finally, a perspective on the challenges and opportunities for NCs-based photocatalysts is provided.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141490071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An ionically cross-linked composite hydrogel electrolyte based on natural biomacromolecules for sustainable zinc-ion batteries†","authors":"Haoyang Ge, Liping Qin, Bingyao Zhang, Long Jiang, Yan Tang, Bingan Lu, Siyu Tian and Jiang Zhou","doi":"10.1039/D4NH00243A","DOIUrl":"10.1039/D4NH00243A","url":null,"abstract":"<p >Zinc-ion batteries (ZIBs) are regarded as promising power sources for flexible and biocompatible devices due to their good sustainability and high intrinsic safety. However, their applications have been hindered by the issues of uncontrolled Zn dendrite growth and severe water-induced side reactions in conventional liquid electrolytes. Herein, an ionically cross-linked composite hydrogel electrolyte based on natural biomacromolecules, including iota-carrageenan and sodium alginate, is designed to promote highly efficient and reversible Zn plating/stripping. The abundant functional groups of macromolecules effectively suppress the reactivity of water molecules and facilitate uniform Zn deposition. Moreover, the composite hydrogel electrolyte exhibits a high ionic conductivity of 5.89 × 10<small>⁻²</small> S cm<small>⁻¹</small> and a Zn<small>²⁺</small> transference number of 0.58. Consequently, the Zn‖Zn symmetric cell with the composite hydrogel electrolyte shows a stable cycle life of more than 500 h. Meanwhile, the Zn‖NH<small>₄</small>V<small>₄</small>O<small>₁₀</small> coin cell with the composite hydrogel electrolyte retains a high specific capacity of approximately 200 mA h g<small>⁻¹</small> after 600 cycles at 2 A g<small>⁻¹</small>. The Zn‖NVO pouch cell based on the composite hydrogel electrolyte also shows a high specific capacity of 246.1 mA h g<small>⁻¹</small> at 0.5 A g<small>⁻¹</small> and retains 70.7% of its initial capacity after 150 cycles. The pouch cell performs well at different bending angles and exhibits a capacity retention rate of 98% after returning to its initial state from 180° folding. This work aims to construct high-performance hydrogel electrolytes using low-cost natural materials, which may provide a solution for the application of ZIBs in flexible biocompatible devices.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":null,"pages":null},"PeriodicalIF":8.0,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}