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Chinese Journal of Polymer Science 2022年第4期40卷 355-364页

作者： Wei-Na Zhang Xiao-Qian Wu Guo Wang Yu-Ai Duan Hua Geng Yi Liao Department of Chemistry Beijing Advanced Innovation Center for Imaging Theory and TechnologyCapital Normal UniversityBeijing 100048China

High-performance ambipolar charge transport materials can reduce the manufacturing cost of OFET and OPV devices,and simplify circuit design and device structure.In order to obtain ambipolar donor-acceptor(D-A)polymer,many efforts have been made through different donor and acceptor combination,halogenation or heteroatom substitution.However,the influencing factor for charge transport polarity is still much complicated.Based on intra-chain super-exchange mechanism for D-A polymer,we found that the energy alignment of donor and acceptor moiety has large impact on charge transport polarity.When the HOMO-LUMO(H-L)gap of the acceptor moiety is narrow,its HOMO/LUMO energy level both lie between the HOMO and LUMO of the donor moiety(sandwich-type energy alignment),and the corresponding D-A copolymers will be more likely ambipolar transport.And thus,take a narrow H-L gap thiazoleisoindigo(TzIID)acceptor as an example,we demonstrated that a series of TzIID based copolymers combined with wide H-L gap donor moieties can reveal ambipolar transport.We further predict several high performance ambipolar D-A copolymers(TzIID-TT etc.)with balanced electron and hole transport,whose effective mass(m_(e)^(*)=0.146 and m_(h)^(*)=0.128)is one of the smallest effective masses among ambipolar materials.

关键词： D-A copolymer Ambipolar Super-exchange mechanism Charge transport

Controlled crystal orientation of two-dimensional Ruddlesden-Popper halide perovskite films for solar cells

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International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 49-58页

作者： Jiuyao Du Mengqi Zhang Jianjun Tian beijing advanced innovation center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Metal halide perovskite solar cells have attracted considerable attention because of their high-power conversion efficiency and costeffective solution-processable fabrication;however,they exhibit poor structural stability.Two-dimensional(2D)Ruddlesden-Popper(RP)perovskites could address the aforementioned issue and present excellent stability because of their hydrophobic organic spacer cations.However,the crystallographic orientation of 2D crystals should be perpendicular to the bottom substrates for charges to transport fast and be collected in solar cells.Moreover,controlling the crystallographic orientation of the 2D RP perovskites prepared by the solution process is difficult.Herein,we reviewed the progress of recent research regarding 2D RP perovskite films with the focus on the crystallographic orientation mechanism and orientation controlling methods.Furthermore,the current issues and prospects of 2D RP perovskites in the photovoltaic field were discussed to elucidate their development and application in the future.

关键词： two-dimensional Ruddlesden-Popper crystallographic orientation perovskite solar cells

Significant influence of trace Li on the mechanical properties, corrosion behavior, and antibacterial properties of biodegradable Zn–4Cu alloys

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Journal of Materials Science & technology 2023年第20期151卷 245-257页

作者： Shiyu Huang Heng Liu Yanjing Su Lijie Qiao Yu Yan beijing advanced innovation center for Materials Genome Engineering Corrosion and Protection CenterInstitute for Advanced Materials and TechnologyUniversity of Science and TechnologyBeijing 100083China

In this work,trace Li was introduced to strengthen Zn–4Cu alloys.The results indicated that trace amounts of Li contributed to a significant increase in strength,resulting in an acceptable loss of elongation at fracture.Additionally,Li in the form of LiZn_(4) led to more intensive galvanic corrosion,which accelerated the early corrosion rate.The release of a large amount of Zn^(2+),caused by the addition of Li,affected the phase composition of the main Zn-containing corrosion products.Moreover,the inhibition effect of the alloy on Staphylococcus aureus(S.aureus)was enhanced by the addition of 0.02 wt.%Li.

关键词： Microalloying Zn-Cu alloy LiZn_(4)/Zn pairs Biodegradable mechanism SKPFM

Intense terahertz radiation: generation and application

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Frontiers of Optoelectronics 2021年第1期14卷 4-36页

作者： Yan ZHANG Kaixuan LI Huan ZHAO Department of Physics Beijing Key Laboratory for Metamaterials and DevicesBeijing Advanced Innovation Center for Imaging Theory and TechnologyCapital Normal UniversityBeijing 100048China

Strong terahertz(THz)radiation provides a powerful tool to manipulate and control complex condensed matter systems.This review provides an overview of progress in the generation,detection,and applications of intense THz radiation.The tabletop intense THz sources based on Ti:sapphire laser are reviewed,including photoconductive antennas(PCAs),optical rectification sources,plasma-based THz sources,and some novel techniques for THz generations,such as topological insulators,spintronic materials,and metasurfaces.The coherent THz detection methods are summarized,and their limitations for intense THz detection are analyzed.Applications of intense THz radiation are introduced,including applications in spectroscopy detection,nonlinear effects,and switching of coherent magnons.The review is concluded with a short perspective on the generation and applications of intense THz radiation.

关键词： terahertz(THz)radiation THz generation THz detection light-matter interaction

Effect of Sn doping concentration on the oxidation of Al-containing MAX phase(Ti_(3)AlC_(2))combining simulation with experiment

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Fundamental Research 2022年第1期2卷 114-122页

作者： Chunyu Guo Enhui Wang Yunsong Liu Yapeng Zheng Tao Yang Xinmei Hou beijing advanced innovation center for Materials Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Sn doping is usually adopted to prepare Ti_(3)AlC_(2)in mass production because it can reduce the synthesis temperature while increasing the phase purity.However,excessive Sn doping usually deteriorates the oxidation resistance of Ti_(3)AlC_(2).Therefore,an appropriate Sn doping concentration is a vital issue.In this work,the effect of Sn doping concentration on the oxidation behavior of Ti_(3)AlC_(2)was systematically investigated by combining theoretical calculations and experimental methods.Density function theory calculations suggest that the oxygen adsorption mechanisms for the(001)surface of Ti_(3)AlC_(2)with and without Sn doping are similar,and Ti-O bonds are always preferentially formed.The molecular dynamics simulation further indicates that Al atoms have a faster diffusion rate during the oxidation process.Therefore,a continuous Al_(2)O_(3)layer can form rapidly at high temperature.Nevertheless,when the Sn doping concentration exceeds 10 mol%,the continuity of the Al_(2)O_(3)layer is destroyed,thereby impairing the oxidation resistance of Ti_(3)AlC_(2).Furthermore,oxidation experiments verify the above results.The oxidation mechanisms of Ti3AlC2 with different Sn doping concentrations are also proposed.

关键词： MAX phase Sn doping Density function theory Molecular dynamics Oxidation resistance

Tunable terahertz transmission behaviors and coupling mechanism in hybrid MoS_(2)metamaterials

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Chinese Physics B 2022年第1期31卷 248-254页

作者：邓雨旺周庆莉梁菀琳张朴婧张存林 Key Laboratory of Terahertz Optoelectronics Ministry of Educationand Beijing Advanced Innovation Center for Imaging Theory and TechnologyDepartment of PhysicsCapital Normal UniversityBeijing 100048China

A hybrid metamaterial with the integration of molybdenum disulfide(MoS_(2))overlayer is proposed to manipulate the terahertz(THz)wave.The simulated results indicate that the introduction of MoS_(2) layer could significantly modify the resonant responses with large resonance red-shift and bandwidth broadening due to the depolarization field effect,especially for the structure on the small permitivity substrate.Additionally,the wide-band modulator in off-resonant region and a switch effect at resonance can be achieved by varying the conductivity of MoS_(2) layer.Further theoretical calculations based on the Lorentz coupling model are consistent with the simulated results,explicating the response behaviors originate from the coupling between MoS_(2) overlayer and the metastructure.Our results could provide a possibility for active control THz modulator and switchable device based on the MoS_(2) overlayer and advance the understanding of the coupling mechanism in hybrid structures.

关键词： terahertz metamaterial MoS_(2) coupling mechanism switchable device

Food-derived protein hydrolysates and peptides:anxiolytic and antidepressant activities,characteristics,and mechanisms

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Food Science and Human Wellness 2024年第3期13卷 1168-1185页

作者： Wenhui Li Yu Xi Junru Wang Yinxiao Zhang He Li Xinqi Liu beijing advanced innovation center for Food Nutrition and Human Health Beijing Engineering and Technology Research Center of Food AdditivesNational Soybean Processing Industry Technology Innovation CenterBeijing Technology and Business UniversityBeijing 100048China

Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.

关键词： Anxiolytic Antidepressant Peptides Protein hydrolysates Neurotransmitter

A novel high-Cr CoNi-based superalloy with superior high-temperature microstructural stability, oxidation resistance and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1373-1381页

作者： Xiaorui Zhang Min Zou Song Lu Longfei Li Xiaoli Zhuang Qiang Feng beijing advanced innovation center for Materials Genome Engineering State Key Laboratory for Advanced MetalsUniversity of Science and Technology BeijingBeijing 100083China

A novel multicomponent high-Cr CoNi-based superalloy with superior comprehensive performance was prepared,and the evaluation of its high-temperature microstructural stability,oxidation resistance,and mechanical properties was conducted mainly using its cast polycrystalline alloy.The results disclosed that the morphology of theγ′phase remained stable,and the coarsening rate was slow during the long-term aging at 900–1000℃.The activation energy forγ′precipitate coarsening of alloy 9CoNi-Cr was(402±51)kJ/mol,which is higher compared with those of CMSX-4 and some other Ni-based and Co-based superalloys.Importantly,there was no indica-tion of the formation of topologically close-packed phases during this process.All these factors demonstrated the superior microstructural stability of the alloy.The mass gain of alloy 9CoNi-Cr was 0.6 mg/cm^(2) after oxidation at 1000℃ for 100 h,and the oxidation resistance was comparable to advanced Ni-based superalloys CMSX-4,which can be attributed to the formation of a continuous Al_(2)O_(3) protective layer.Moreover,the compressive yield strength of this cast polycrystalline alloy at high temperatures is clearly higher than that of the conventional Ni-based cast superalloy and the compressive minimum creep rate at 950℃ is comparable to that of the conventional Ni-based cast superalloy,demonstrating the alloy’s good mechanical properties at high temperature.This is partially because high Cr is bene-ficial in improving theγandγ′phase strengths of alloy 9CoNi-Cr.

关键词： CoNi-based superalloys microstructure coarsening oxidation mechanical properties

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激光选区熔化技术制备高熵合金的研究进展

Science China Materials 2023年第11期66卷 4165-4181页

作者：宋鑫芳张勇 beijing advanced innovation center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

高熵合金的多组分特性使其具有许多传统合金无法比拟的优异性能.然而,高熵合金传统的制备方法仍存在一定的局限性.激光选区熔化(SLM)技术可以通过逐层沉积的方式实现复杂零件的精密成形.将SLM技术与高熵合金相结合,可以充分发挥高熵合... 详细信息

高熵合金的多组分特性使其具有许多传统合金无法比拟的优异性能.然而,高熵合金传统的制备方法仍存在一定的局限性.激光选区熔化(SLM)技术可以通过逐层沉积的方式实现复杂零件的精密成形.将SLM技术与高熵合金相结合,可以充分发挥高熵合金的性能优势.本文综述了SLM制备的高熵合金的显微结构和性能特征.由于SLM工艺存在高温梯度和高冷却速率,所以在SLM制备的高熵合金中通常会形成复杂的微观结构,包括胞状亚结构、析出相、层错和纳米孪晶.此外,独特的微观结构为高熵合金带来了优异的力学性能和其他功能,表明利用SLM技术制备高熵合金具有很大的发展潜力.此外,我们还简要介绍了SLM制备的高熵合金的微观缺陷及其应用.本文为高性能高熵合金的设计提供了有益的指导.

关键词： high-entropy alloys selective laser melting micro-structure characteristics performance characteristics potential applications

Local chemical ordering and its impact on radiation damage behavior of multi-principal element alloys

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Journal of Materials Science & technology 2023年第4期135卷 13-25页

作者： Leqing Liu Xiongjun Liu Qing Du Hui Wang Yuan Wu Suihe Jiang Zhaoping Lu beijing advanced innovation center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

Multi-principal element alloys(MPEAs)have attracted much attention as future nuclear materials due to their extraordinary radiation resistances.In this work,we have elucidated the development of local chemical orderings(LCOs)and their influences on radiation damage behavior in the typical CrFeNi MPEA by hybrid-molecular dynamics and Monte Carlo simulations.It was found that considerable LCOs consist-ing of the Cr-Cr and Ni-Fe short-range orders existed in the ordered configuration with optimized system energy.Through modeling the accumulation cascades up to 1000 recoils,we revealed that the size of de-fect clusters and dislocation loops is smaller in the ordered configuration than those in the random one,although the former formed more Frenkel pairs(i.e.,self-interstitials and vacancies).In addition,the dis-tribution of dislocation loops is relatively more dispersed in the ordered configuration,and the stair-rod dislocations related to irradiation swelling are also smaller,implying that the existence of LCOs is con-ducive to enhancing radiation damage tolerance.To understand the underlying mechanism,the effects of LCOs on the formation and evolution of defects and radiation resistance were discussed from the aspects of atomic bonding,migration path,and energy of defect diffusion,which provides theoretical guidance for the design of MPEAs with enhanced radiation resistance.

关键词： Multi-principal element alloys Local chemical ordering Radiation damage Dislocation evolution Molecular dynamics simulation