检索结果-内蒙古大学图书馆

Large focal length planar focusing of Dyakonov polaritons in hyperbolic metamaterial

Progress in Natural science:materials International 2024年第4期34卷 632-636页

作者： Xiaoyu Xiong Yihang Fan Weipeng Wang Yongzheng Wen Zhengjun Zhang Jingbo Sun Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University

Achieving subwavelength optical focusing is of great importance in nanophotonics. However, achieving focusing with both a small focal spot size and a large focal length remains elusive so far. Here, a large focal length planar focusing device is presented, utilizing highly oriented Dyakonov polaritons in hyperbolic metamaterial with periodic silver rings as the excitation source. Experimental results show that by controlling the size of the excitation sources, the focal length can reach 6λ0（where λ0is the illumination wavelength）, and the focal spot size can be reduced to λ0/10. This method provides new prospects for planar polariton optical applications.

关键词： Subwavelength optical focusing Dyakonov polaritons In-plane hyperbolic metamaterials Near-field optics

来源：评论

学校读者我要写书评

暂无评论

Dual heterogeneous structure enabled ultrahigh strength and ductility across a broad temperature range in CrCoNi-based medium-entropy alloy

引用

材料科学技术（英文版） 2025年第4期207卷 46-59页

作者： Kang Tu Bo Li Zonglin Li Kaisheng Ming Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China

Developing alloys with exceptional strength-ductility combinations across a broad temperature range is crucial for advanced structural *** emerging face-centered cubic medium-entropy alloys(MEAs)demonstrate outstanding mechanical properties at both ambient and cryogenic *** are anticipated to extend their applicability to elevated temperatures,owing to their inherent ad-vantages in leveraging multiple strengthening and deformation ***,a dual heterostructure,comprising of heterogeneous grain structure with heterogeneous distribution of the micro-scale Nb-rich Laves phases,is introduced in a CrCoNi-based MEA through thermo-mechanical ***,a high-density nano-coherent γ'phase is introduced within the grains through isothermal aging *** superior thermal stability of the heterogeneously distributed precipitates enables the dual heterostructure to persist at temperatures up to 1073 K,allowing the MEA to maintain excellent mechan-ical properties across a wide temperature *** yield strength of the dual-heterogeneous-structured MEA reaches up to 1.2 GPa,1.1 GPa,0.8 GPa,and 0.6 GPa,coupled with total elongation values of 28.6％,28.4％,12.6％,and 6.1％at 93 K,298 K,873 K,and 1073 K,*** high yield strength primar-ily stems from precipitation strengthening and hetero-deformation-induced *** high flow stress and low stacking fault energy of the dual-heterogeneous-structured MEA promote the formation of high-density stacking faults and nanotwins during deformation from 93 K to 1073 K,and their den-sity increase with decreasing deformation *** greatly contributes to the enhanced strain-hardening capability and ductility across a wide temperature *** study offers a practical solu-tion for designing dual-heterogeneous-structured MEAs with both high yield strength and large ductility across a wide temperature range.

关键词： Medium-entropy alloy Dual heterogeneous structure Strength-ductility synergy Cryogenic temperatures Elevated temperatures

来源：评论

学校读者我要写书评

暂无评论

Quantum Dots Mediated Crystallization Enhancement in Two-Step Processed Perovskite Solar Cells

引用

Nano-Micro Letters 2025年第7期17卷 350-362页

作者： Heng Liu Geyu Jin Jiantao Wang Weihai Zhang Long Qing Yao Zhang Qiongqiong Lu Pengfei Yue Guoshang Zhang Jing Wei Hongbo Li Hsing-Lin Wang Henan Key Laboratory of Advanced Conductor Materials Institute of MaterialsHenan Academy of Sciences Department of Materials Science and Engineering Southern University of Science and Technology Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications Experimental Center of Advanced MaterialsSchool of Materials Science and EngineeringBeijing Institute of Technology College of New Energy Ningbo University of Technology

Hybrid organic–inorganic lead halide perovskites have emerged as a promising material for high-efficiency solar cells, yet challenges related to crystallization and defects limit their performance and stability. This study investigates the use of perovskite quantum dots（QDs） as crystallization seeds to enhance the quality of FAPbI3perovskite films and improve the performance of perovskite solar cells（PSCs）. We demonstrate that CsPbI3and CsPbBr3QDs effectively guide the crystallization process, leading to the formation of larger crystals with preferential orientations, particularly the（001） and（002） planes, which are associated with reduced defect densities. This seedmediated growth strategy resulted in PSCs with power conversion efficiencies（PCEs） of 24.75% and 24.11%, respectively, compared to the baseline efficiency of 22.05% for control devices. Furthermore, devices incorporating QD-treated perovskite films exhibited remarkable stability, maintaining over 80% of their initial PCE after 1000 h of simulated sunlight exposure, a significant improvement over the control. Detailed optoelectronic characterization revealed reduced non-radiative recombination and enhanced charge transport in QD-treated devices. These findings highlight the potential of QDs as a powerful tool to improve perovskite crystallization, facet orientation, and overall device performance, offering a promising route to enhance both efficiency and stability in PSCs.

关键词： Crystallization Efficiency Perovskite solar cells Quantum dots Stability Two-step

来源：评论

学校读者我要写书评

暂无评论

Ultrathin and capacity-tunable lithium metal wires for lithium-based fiber batteries

引用

National science Review 2025年第3期12卷 274-283页

作者： Chuanfa Li Qian Ye Jiaqi Wang Xinlin Huang Tianbing Song Kun Zhang Pengzhou Li Yanan Zhang Xiaocheng Gong Yi Jiang Yue Gao Huisheng Peng Bingjie Wang State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Institute of Fiber Materials and Devices and Laboratory of Advanced Materials Fudan University

Ultrathin lithium（Li） metal wires with tunable capacities have great promise for precise prelithiation of fiber anodes and high-energy-density Li-based fiber batteries. However, the application of Li metal in fiber batteries faces great challenges due to its mechanical fragility and the resulting limited micro-dimension manufacturing capability. These challenges impede the production of ultrathin Li wires with adjustable Li contents to match the capacities of Li-based fiber batteries. Herein, silver-plated aramid yarns（Ag/AYs） are employed to load Li metal for producing ultrathin Li wires. The bundled structure of Ag/AYs leads to the adjustable volume of oriented voids within the fibers, thus resulting in accurately tunable capacities(0.0048–2.4 m Ah cm-1) and diameters（20–534 μm） of Li wires. Such thin Li wires are used to precisely compensate for Li loss during the formation cycle of the fiber graphite anodes, thereby improving the initial Coulombic efficiency from ～88% to ～100%. Additionally, when employed as anodes, these Li wires enabled the fiber batteries to exhibit exceptional cycling stability for 150 cycles under a relatively low negative/positive ratio of 2.06, while achieving a high energy density of 139.822 Wh kg-1based on the total mass of the battery.

关键词： ultrathin Li wires tunable capacities precise prelithiation high-energy-density fiber batteries

来源：评论

学校读者我要写书评

暂无评论

Effects of longitudinal magnetic field on primary dendrite spacing and segregation of directionally solidified single crystal superalloy

引用

Progress in Natural science:materials International 2024年第1期34卷 26-36页

作者： Congjiang Zhang Yilin Zhou Chen Shen Weili Ren Xiaotan Yuan Biao Ding Haibiao Lu Zuosheng Lei Yunbo Zhong Ang Zhang State Key Laboratory of Advanced Special Steel College of Materials Science and Engineering Shanghai University National Engineering Research Center for Magnesium Alloys Natural Key Laboratory of Advanced Casting Technologies College of Materials Science and EngineeringChongqing University

The primary dendrite spacing(PDS) and segregation of directionally solidified single crystal(SC) superalloy under the longitudinal magnetic field(LMF) were investigated based on the analysis of the whole cross-sectional microstructure at different solidification distances. The results show that the PDS under the LMF remains basically unchanged at different solidification distances, and it is greater than that under no LMF. With the increase of magnetic field intensity, the PDS increases and the macrosegregation decreases. The increasing PDS and reducing segregation under the LMF can be attributed to the increase of solute boundary layer, which expands the non-equilibrium freezing temperature range and brings the effective partition coefficient closer to 1. The increase of the solute enrichment layer thickness could be caused by the downward secondary circulation generated by the thermoelectric magnetic convection(TEMC) near the interface, which drives the migration of solutes towards the interdendritic region. This work not only clarifies the mechanism of LMF controlling PDS and reducing segregation by TEMC, but also provides theoretical guidance for producing high-quality SC superalloys using magnetic fields.

关键词： Primary dendrite spacing Segregation Single crystal superalloy Directional solidification Magnetic field Thermoelectric magnetic convection

来源：评论

学校读者我要写书评

暂无评论

Reverse modulation of defect density of Ce-MOF-808 by solvent-assisted ligand exchange for dicyclopentadiene hydrogenation

引用

science China Chemistry 2025年第6期68卷 2744-2756页

作者： Danfeng Zhao Fajie Hu Rushuo Li Xinmeng Xu Zhaokun Wang Zuoshuai Xi Jun Tong Xiubing Huang Ge Wang Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 °C and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.

关键词： defects metal-organic-frameworks ligand exchange porous frustrated Lewis pairs (FLPs) selective hydrogenation

来源：评论

学校读者我要写书评

暂无评论

Li Alloys in All Solid-State Lithium Batteries:A Review of Fundamentals and Applications

引用

Electrochemical Energy Reviews 2024年第1期7卷 586-623页

作者： Jingru Li Han Su Yu Liu Yu Zhong Xiuli Wang Jiangping Tu State Key Laboratory of Silicon and Advanced Semiconductor Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang ProvinceSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina

All solid-state lithium batteries(ASSLBs)overcome the safety concerns associated with traditional lithium-ion batteries and ensure the safe utilization of high-energy-density electrodes,particularly Li metal anodes with ultrahigh specific ***,the practical implementation of ASSLBs is limited by the instability of the interface between the anode and solid-state electrolyte(SSE).To mitigate this,considerable research has been dedicated to achieving enhanced stability at the anode/SSE *** the current strategies for enhancing interface performance,the concept of Li-alloy materials is extensively used and well functionalized in various scenarios,including Li alloys as anodes,Li-alloy interlayers and Li alloys in the *** the notable achievements of Li-alloy materials in ASSLBs,the functionality,practicality and working mechanism of Li-alloys have not been fully *** review commences by providing an exhaustive and in-depth examination of the fundamental kinetics,thermodynamics,and mechanics,highlighting Li-alloy ***,through a systematic interconnection of material properties and their practical applications,we undertake a comprehensive analysis of the operative principles governing Li *** analytical approach allows a thorough evaluation of the viability and utility of Li alloys within the context of ***,this review concludes by succinctly summarizing the future prospects and inherent potential of Li-alloy materials for further advancing the field of ASSLBs.

关键词： Li alloys Anode All-solid-state lithium batteries Physicochemical properties Applications

来源：评论

学校读者我要写书评

暂无评论

Progress on the program of Si-compatible two-dimensional semiconductor materials and devices

引用

science China(Information sciences) 2024年第6期67卷 152-171页

作者： Mingsheng XU Yuwei WANG Jiwei LIU Deren YANG College of Integrated Circuits State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University School of Materials Science and Engineering State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University

Two-dimensional(2D) materials are at the forefront of innovation, heralding a new era for nextgeneration electronics and optoelectronics. These materials are distinguished by their unique structural characteristics: they have no hanging bonds on their surface, exhibit weakened electrostatic shielding in the Z-direction, and boast atomic thickness in their monolayers. These features have led to groundbreaking discoveries in electrical, optical, and magnetic properties, paving the way for advancements in low-power electronics, valleytronics, infrared detectors, and memory devices. Despite these promising developments,Si-based technologies continue to dominate the landscape of next-generation electronics and optoelectronics,as well as heterogeneous integration. In response to this ongoing evolution, the National Natural science Foundation of China(NSFC) initiated a major program in 2021 dubbed “Si-compatible two-dimensional semiconductor materials and devices”. This study reviews the progress made under the NSFC Program,spotlighting its main achievements and outlining key future research directions. Additionally, it sheds light on the challenges that researchers in the 2D domain face, particularly in developing Si-compatible 2D technologies.

关键词： two-dimensional materials Si-based CMOS technologies electronics and optoelectronics heterogeneous integration low-power

来源：评论

学校读者我要写书评

暂无评论

Obtaining extremely low coercivity of high Bs FeCoBSiCPCu nanocrystalline alloys through modulation of magnetic anisotropy

引用

材料科学技术（英文版） 2025年第4期207卷 105-112页

作者： Mingjuan Cai Zhijun Guo Lei Li Xingyu Zheng Xiaoxuan Yang Qianqian Liu Gaopeng Zou Baolong Shen School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing 211189PR China

Longitudinal magnetic field annealing is utilized for modifying the magnetic anisotropy and enhancing the magnetic softness of Fe75Co8(B10Si3C3P1)1-x/17Cux(x=0.5,0.75,1,1.25)nanocrystalline *** of the magnetic field-annealed nanocrystalline alloys with Cu content more than 0.5 at.％exhibit signifi-cantly improved soft-magnetic properties,including high saturation magnetic flux density up to 1.87 T,effective permeability of 13,000-16,000 under the condition of 1 A/m and 1 kHz,coercivity as low as 1.6 A/m,and core loss of 0.11-0.45 W/kg under the condition of 1.0 T and 50 *** application of a magnetic field promotes the nucleation and inhibits the growth of grains,leading to an increase in the number density of nanocrystals and the crystalline volume fraction,and a reduction in the grain *** magnetic field annealing reduces the effective magneto-crystalline anisotropy energy to 2-4 J/m3,and induces longitudinal magnetic anisotropy with anisotropy energy density of 400-900 J/m3 which shows dependence on the crystalline volume *** field-induced magnetic anisotropy dominates over the random local magnetic anisotropies,and results in the formation of regular magnetic domains aligned longitudinally,pinning-free domain wall displacement,and thus enhanced soft-magnetic proper-ties.

关键词： Nanocrystalline alloy Magnetic anisotropy Magnetic field annealing Soft-magnetic property Microstructure

来源：评论

学校读者我要写书评

暂无评论

Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

引用

Chinese Journal of Polymer science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang Wen-Qing Wang Jia-Ping Lin Li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：