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Highly selective[4+4]cross-photodimerization of(4a-azonia)anthracenes driven by confinement of D-A hetero-guest pair in cucurbituril host

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Chinese Chemical Letters 2025年第3期36卷 263-266页

作者： Xianchen Hu Junli Yang Fang Gao Zhiyong Zhao Simin Liu School of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China The State Key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan 430081China

The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side ***,we report a series of highly selective[4+4]cross-photodimerization between anthracene and 4a-azoniaanthracene derivatives within a cucurbit[10]uril(CB[10])host in *** inclusion complexes were formed through encapsulation of donor(D1-D2,anthracene derivative)and acceptor(A1-A3,4a-azoniaanthracene derivatives)pairs in CB[10].In the presence of CB[10](1.0 equiv.),the[4+4]cross-photodimerization between D1 and A1/A2/A3 efficiently gave a single racemic ***,the cross-photodimerization between 9-substituted anthracene D2 and A1/A3 was catalyzed by CB[10](0.1 equiv.)to quantitatively yield a cross-photodimer with high *** formation of selective cross-photodimers could be attributed to the exclusive encapsulation of D-A hetero-guest pairs in CB[10]and the confinement effect of the CB[10]host *** study further proves host–guest complexation as a powerful strategy for cross-cycloaddition reactions with high efficiency.

关键词： Supramolecular catalysis Cross-photodimerization Host-guest complexation Charge-transfer interaction Cucurbituril

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Four directional circular optical phased array for uniform two-dimensional beam steering at visible wavelength

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Optics Express 2025年第7期33卷 15954-15963页

作者： Zhang, Qianhan Lian, Daixin Xu, Zixu Zhao, Shi Chen, Jingye Dai, Daoxin Shi, Yaocheng State Key Laboratory for Extreme Photonics and Instrumentation Center for Optical and Electromagnetic Research International Research Center for Advanced Photonics College of Optical Science and Engineering Zhejiang University Hangzhou310058 China

Optical phased arrays (OPAs), owing to their remarkable capacity for rapid and precise beam steering, have emerged as a pivotal technology in various applications such as augmented reality, free-space optical communication, and optical imaging. In this paper, we present a 64-element two-dimensional (2D) circular OPA operating at a visible wavelength of 632.5 nm. To the best of our knowledge, this is the first time that 2D continuous beam steering with pure phase control has been realized at the visible wavelengths. We propose arrowhead antennas to reduce residual energy while maintaining the integrity of the far-field pattern. Furthermore, a four-directional array arrangement has been introduced to expand the field of view and enhance the uniformity of the side lobe suppression ratio (SLSR) at different azimuth angles. The measurement for the fabricated OPA shows 2D beam steering with an elevation angle of 9° and an azimuth angle of 360° with an SLSR of over 3 dB. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Antenna phased arrays

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Tungsten-substituted zeolite-regulated unsaturated cobalt atoms for robust light alkane dehydrogenation

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Journal of Energy Chemistry 2025年第4期103卷 525-534页

作者： Xichen Yin Tianjun Zhang Yanhang Ma Qiming Sun Innovation Center for Chemical Science College of Chemistry Chemical Engineering and Materials Science Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow University State Key Laboratory of New Pharmaceutical Preparations and Excipients College of Chemistry and Materials Science Hebei University Shanghai Key Laboratory of High-resolution Electron Microscopy & School of Physical Science and Technology Shanghai Tech University

The dehydrogenation of alkanes has emerged as a vital complementary process to address the increasing global demand for olefins.A key challenge remains in the construction of novel active centers that offer superior activity,stability,and ***,tricoordinated cobalt atoms were successfully fabricated through an in-situ ligand-protected synthesis by introducing tungsten atoms into zeolite *** unsaturated Co species efficiently activate C-H bonds while suppressing C-C bond cleavage,resulting in exceptional catalytic activity and olefin selectivity in both propane and ethane dehydrogenation *** optimized Co0.2%@0.01W-S-1 catalyst demonstrated an impressive propylene formation rate of 15.2 molC3H6gcC h-1at 823 K and an ethylene formation rate of 240.3molC2H4gCo-1h-1at 913 K,with propylene and ethylene selectivities of 99.0% and 97.5%,*** results not only significantly surpass conventional tetracoordinated Co catalysts but also rival some Pt-based catalysts under similar ***,the catalyst exhibited excellent stability in dehydrogenation reactions,with no significant loss in catalytic activity after five consecutive regeneration *** work offers valuable insights into the design of zeolite-supported non-precious metal catalysts with high activity and durability for efficient alkane dehydrogenation.

关键词： Ethane dehydrogenation Heterogeneous catalysis Propane dehydrogenation Tricoordinated cobalt Tungsten-substituted zeolite

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Recent advances in photopolymerization 3D printing of alumina-ceramic

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Progress in Natural Science:Materials International 2025年第1期35卷 1-30页

作者： M.Irfan Hussain Min Xia XiaoNa Ren Zhen Shen Muhammad Jamil Changchun Ge Institute of Powder Metallurgy and Advanced Ceramics School of Material Science and Engineering University of Science and Technology Beijing State Key Laboratory of Multimodal Artificial Intelligence Systems Beijing Engineering Research Center of Intelligent Systems and Technology Institute of AutomationChinese Academy of Sciences College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Digital light processing(DLP) 3D printing has a huge potential for manufacturing intricate and customized ceramic parts with high precision and cost-effectiveness. Research in this field contributes to material innovation,opening the avenues for new process designs in both scientific and industrial sectors. However, the implementation of DLP 3D printing technology in ceramic research has not yet reached the maturity level as that in polymer and tissue engineering. Necessarily, a holistic in-depth literature reporting the successful integration of alumina ceramics within DLP 3D printing technology is urgently needed. This review, systematic examines recent progress in DLP technology, focusing on photopolymer resins that incorporate UV-sensitive monomers, photoinitiators, and dispersants, as well as their synergistic effects on achieving high-quality printing, desirable material properties, and enhanced performance. Further, the review discusses key factors including post-processing characteristics such as debinding and sintering, which influence microstructure, and defect formation including microcracks, porosity and voids. Finally, the challenges associated with printing and sintering are highlighted,aiming to identify focused focused development pathways and potential solution to optimize outcomes. This analysis clarifies existing challenges and also propsoes future applications for DLP technology in the aluminaceramic field.

关键词： Al2O3 ceramics Applications Digital light processing (DLP) Post-processing Resin

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Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia Xie Chengjia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

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Observation of tunable exceptional points in a non-Hermitian acoustic system

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Science China(Physics,Mechanics & Astronomy) 2025年第5期Mechanics & Astronomy) .卷 147-154页

作者： Chen Liu Zhongming Gu Haixiao Zhang Xiaowei Zhang Chuanhao Ge Tuo Liu Jie Zhu Institute of Acoustics School of Physics Science and Engineering Tongji University State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences School of Physics MOE Key Laboratory of Modern Acoustics Collaborative Innovation Center of Advanced MicrostructuresNanjing University School of Electrical and Information Engineering Changzhou Institute of Technology Key Laboratory of Speech Acoustics and Content Understanding Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences

Exceptional points(EPs) have extensive and important applications in many wave-based technologies, such as ultra-sensitive sensing, unidirectional scattering and low-threshold laser. However, most of the previous EP-related wave phenomena are demonstrated in systems with fixed configuration, thereby extremely constraining their adaptability and reconfigurability in ***, we introduce a flexible approach to tuning EPs in an acoustic system with sandwich structures. A rotatable component,associated with an alterable gradient index, is clamped by a pair of lossy acoustic resonators. Theoretical derivations and numerical simulations validate the capabilities of the model in continuously regulating EPs in the parameter space, with ingenious experimental setups confirming these findings. The results showcase the system's effectiveness in achieving unidirectional reflectionless wave propagation across various frequencies. Our research reveals a flexible approach to linking the adjustment of EPs to a simple structural parameter, offering a robust framework for exploring and implementing non-Hermitian wave phenomena in practical scenarios.

关键词： asymmetric reflection tunable exceptional points non-Hermitian acoustic system

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Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou Yang Dai Guoyao Yue Yiman Zhang Lulu Li Zhong-Zhen Yu Peng Min Hao-Bin Zhang State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

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Kinetic investigation of the energy storage process in graphene fiber supercapacitors:Unraveling mechanisms,fabrications,property manipulation,and wearable applications

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Carbon Energy 2025年第1期7卷 133-173页

作者： Juan Zhang Wenwen Liu Minzhi Du Qingli Xu Minren Hung Ruifang Xiang Meng Liao Xinhou Wang Bingjie Wang Aiping Yu Kun Zhang Key Laboratory of Textile Science and Technology(Donghua University) Ministry of EducationCollege of TextilesDonghua UniversityShanghaiChina Department of Chemical Engineering Waterloo Institute for NanotechnologyUniversity of WaterlooWaterlooONCanada Laboratory of Advanced Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of Macromolecular ScienceFudan University2205 Songhu RdShanghai 200438China College of Mechanical Engineering Donghua UniversityShanghai 201620China

Graphene fiber supercapacitors(GFSCs)have garnered significant attention due to their exceptional features,including high power density,rapid charge/discharge rates,prolonged cycling durability,and versatile weaving ***,inherent challenges in graphene fibers(GFs),particularly the restricted ion-accessible specific surface area(SSA)and sluggish ion transport kinetics,hinder the achievement of optimal capacitance and rate *** existing reviews on GFSCs,a notable gap exists in thoroughly exploring the kinetics governing the energy storage process in *** review aims to address this gap by thoroughly analyzing the energy storage mechanism,fabrication methodologies,property manipulation,and wearable applications of *** theoretical analysis of the energy storage process,specific parameters in advanced GF fabrication methodologies are carefully summarized,which can be used to modulate nano/micro-structures,thereby enhancing energy storage *** particular,enhanced ion storage is realized by creating more ion-accessible SSA and introducing extra-capacitive components,while accelerated ion transport is achieved by shortening the transport channel length and improving the accessibility of electrolyte *** on the established structure-property relationship,several critical strategies for constructing optimal surface and structure profiles of GF electrodes are *** on the exceptional flexibility and wearability of GFSCs,the review further underscores their potential as foundational elements for constructing multifunctional e-textiles using conventional textile *** conclusion,this review provides insights into current challenges and suggests potential research directions for GFSCs.

关键词： fiber-shaped supercapacitor graphene ion storage ion transport wearable application

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Boron cluster-based TADF emitter via through-space charge transfer enabling efficient orange-red electroluminesce

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Chinese Chemical Letters 2025年第3期36卷 232-238页

作者： Xiao Yu Dongyue Cui Mengmeng Wang Zhaojin Wang Mengzhu Wang Deshuang Tu Vladimir Bregadze Changsheng Lu Qiang Zhao Runfeng Chen Hong Yan State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory for Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Jiangsu National Synergistic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts&TelecommunicationsNanjing 210023China Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of TechnologyYancheng 224051China College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts&TelecommunicationsNanjing 210023China A.N.Nesmeyanov Institute of Organoelement Compounds(INEOS) Russian Academy of SciencesMoscow 119991Russia

Thermally activated delayed fluorescence(TADF)materials driven by a through-space charge transfer(TSCT)mechanism have garnered wide ***,access of TSCT-TADF molecules with longwavelength emission remains a formidable *** this study,we introduce a novel V-type DA-D-A’emitter,Trz-mCzCbCz,by using a carborane *** design strategically incorporates carbazole(Cz)and 2,4,6-triphenyl-1,3,5-triazine(Trz)as donor and acceptor moieties,*** calculations alongside experimental validations affirm the typical TSCT-TADF characteristics of this *** to the unique structural and electronic attributes of carboranes,Trz-mCzCbCz exhibits an orange-red emission,markedly diverging from the traditional blue-to-green emissions observed in classical Cz and Trz-based TADF ***,bright emission in aggregates was observed for Trz-mCzCbCz with absolute photoluminescence quantum yield(PLQY)of up to 88.8%.As such,we have successfully fabricated five organic light-emitting diodes(OLEDs)by utilizing Trz-mCzCbCz as the emitting *** is important to note that both the reverse intersystem crossing process and the TADF properties are profoundly influenced by host *** fabricated OLED devices reached a maximum external quantum efficiency(EQE)of 12.7%,with an emission peak at 592 *** represents the highest recorded efficiency for TSCT-TADF OLEDs employing carborane derivatives as emitting layers.

关键词： Thermally activated delayed fluorescence Through-space charge transfer Carborane Boron clusters Organic light-emitting diodes

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Modulated synthesis of stoichiometric and sub-stoichiometric two-dimensional covalent organic frameworks for enhanced ethylene purification

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Chinese Chemical Letters 2025年第1期36卷 272-276页

作者： Jiahao Li Guinan Chen Chunhong Chen Yuanyuan Lou Zhihao Xing Tao Zhang Chengtao Gong Yongwu Peng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China

Controlled synthesis of two-dimensional covalent organic frameworks(2D COFs),including stoichiometric and sub-stoichiometric variations,is a topic of growing interest due to its potential in gas separation *** this study,we successfully synthesized three distinct 2D COFs by carefully adjusting solvent compositions and monomer ratios during the synthesis of[4+4]type *** included a stoichiometric[4+4]type COF and two sub-stoichiometric[4+2]type COFs,featuring unreacted amino or formyl *** resulting COFs exhibit different gas adsorption and separation ***,sub-stoichiometric COF-DA with residual amino groups shows comparable adsorption capacity for C_(2)H_(2),C_(2)H_(4),and CO_(2)to stoichiometric *** contrast,sub-stoichiometric COF-Py with residual formyl groups displays enhanced adsorption selectivity for C_(2)H_(2)/C_(2)H_(4)and C_(2)H_(2)/CO_(2)separation,with the C_(2)H_(2)/C_(2)H_(4)selectivity being the highest among reported COFs,attributed to increased pore polarity resulting from the presence of formyl *** study not only offers an additional example of substoichiometric COF synthesis but also advocates for further exploration of sub-stoichiometric COF materials,particularly in the field of gas adsorption and separation.

关键词： Two-dimensional covalent organic frameworks Stoichiometric and sub-stoichiometric Residual functional groups Ethylene purification

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