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National Science Review 2024年第2期11卷 65-80页

作者： Chaowei Hu Tiema Qian Ni Ni Department of Physics and Astronomy and California Nano Systems Institute University of California-Los Angeles

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators,etc. To date, the MnBi2nTe3n+1family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

关键词： MnBi2Te4 magnetic topological insulator magnetism tuning antiferromagnetism ferromagnetism pressure chemical doping

Opening Band Gap of Graphene by chemical doping: a First Principles Study

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Chinese Journal of Structural Chemistry 2014年第4期33卷 513-518页

作者：管小敏张红雨张孟罗有华 Department of Physics East China University of Science and Technology

Single atom chemically doped graphene has been theoretically studied by density functional theory. The largest band gap, 0.62 eV, appears in arsenic atom doped graphene, then 0.60 eV comes by the tin atom, whose deformations can neither be ignored. It is also found that oxygen and iron single atom embedded graphene can open band gap by 0.52 and 0.54 eV, respectively. Moreover, doping O atom shows little distortion and high stability by charge redistribution. The band gap of Fe doped graphene is opened by orbital hybridization. The other heteroatom doped results are a little inferior to them.

关键词： grapheme chemical doping DFT band gap

多带笼目超导体CsV_(3)Sb_(5)衍生体系的可调磁通涡旋束缚态

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Science Bulletin 2024年第7期69卷 885-892页

作者：黄子豪韩相和赵振刘锦锦李鹏飞谭恒心王秩伟姚裕贵杨海涛颜丙海蒋坤胡江平汪自强陈辉高鸿钧 Beijing National Center for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems Beijing Institute of TechnologyBeijing 100081China Department of Condensed Matter Physics Weizmann Institute of ScienceRehovot 7610001Israel Hefei National Laboratory Hefei 230088China Department of Physics Boston CollegeChestnut Hill MA 02467USA

Vortices and bound states offer an effective means of comprehending the electronic properties of superconductors.Recently,surface-dependent vortex core states have been observed in the newly discovered kagome superconductors CsV_(3)Sb_(5).Although the spatial distribution of the sharp zero energy conductance peak appears similar to Majorana bound states arising from the superconducting Dirac surface states,its origin remains elusive.In this study,we present observations of tunable vortex bound states(VBSs)in two chemically-doped kagome superconductors Cs(V_(1-x)Tr_(x))_(3)Sb_(5)(Tr=Ta or Ti),using low-temperature scanning tunneling microscopy/spectroscopy.The CsV_(3)Sb_(5)-derived kagome superconductors exhibit full-gap-pairing superconductivity accompanied by the absence of long-range charge orders,in contrast to pristine CsV_(3)Sb_(5).Zero-energy conductance maps demonstrate a field-driven continuous reorientation transition of the vortex lattice,suggesting multiband superconductivity.The Ta-doped CsV_(3)Sb_(5)displays the conventional cross-shaped spatial evolution of Caroli-de Gennes-Matricon bound states,while the Tidoped CsV_(3)Sb_(5)exhibits a sharp,non-split zero-bias conductance peak(ZBCP)that persists over a long distance across the vortex.The spatial evolution of the non-split ZBCP is robust against surface effects and external magnetic field but is related to the doping concentrations.Our study reveals the tunable VBSs in multiband chemically-doped CsV_(3)Sb_(5)system and offers fresh insights into previously reported Y-shaped ZBCP in a non-quantum-limit condition at the surface of kagome superconductor.

关键词： Kagome superconductor chemical doping Vortex lattice transition Vortex bound states Majorana bound states

Active-site and interface engineering of cathode materials for aqueous Zn–gas batteries

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Nano Research 2023年第2期16卷 2325-2346页

作者： Wenxian Liu Jinxiu Feng Tianran Wei Qian Liu Shusheng Zhang Yang Luo Jun Luo Xijun Liu College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China Ministry of Education(MOE)Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials and Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsSchool of ResourceEnvironmentsand MaterialsGuangxi UniversityNanning 530004China Institute for Advanced Study Chengdu UniversityChengdu 610106China College of Chemistry Zhengzhou UniversityZhengzhou 450000China Empa Swiss Federal Laboratories for Materials Science and TechnologySwiss Federal Institute of Technology in Zurich(ETH)DomainDübendorf CH-8600Switzerland Hong Kong Productivity Council(HKPC) Hong Kong 999077China School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China

Aqueous rechargeable Zn–gas batteries are regarded as promising energy storage and conversion devices due to their high safety and inherent environmental friendliness.However,the energy efficiency and power density of Zn–gas batteries are restricted by the kinetically sluggish cathode reactions,such as oxygen evolution reaction(OER)during charging and oxygen reduction reaction(ORR)/carbon dioxide reduction reaction(CO_(2)RR)/nitrogen reduction reaction(NRR)/nitric oxide reduction reaction(NORR)during discharge.In this review,battery configurations and fundamental reactions in Zn–gas batteries are first introduced,including Zn–air,Zn-CO_(2),Zn-N_(2),and Zn-NO batteries.Afterward,recent advances in active site engineering for enhancing the intrinsic catalytic activities of cathode catalysts are summarized.Subsequently,the structure and surface regulation strategies of cathode materials for optimizing the three-phase interface and improving the performance of Zn–gas batteries are discussed.Finally,some personal perspectives for the future development of Zn–gas batteries are presented.

关键词： Zn–gas batteries electrocatalysis single-atom catalysts chemical doping heterostructure interface

Slight Co-doping tuned magnetic and electric properties on cubic BaFeO_(3) single crystal

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Chinese Physics B 2022年第9期31卷 141-145页

作者：覃湜俊周博文刘哲宏叶旭斌张雪强潘昭龙有文 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

The single crystal of cubic perovskite BaFeO3 shows multiple magnetic transitions and external stimulus sensitive magnetism.In this paper,a 5%-Co-doped BaFeO_(3)(i.e.BaFe_(0.95)Co_(0.05)O_(3))single crystal was grown by combining floating zone methods with high-pressure techniques.Such a slight Co doping has little effect on crystal structure,but significantly changes the magnetism from the parent antiferromagnetic ground state to a ferromagnetic one with the Curie temperature TC≈120 K.Compared with the parent BaFeO3 at the induced ferromagnetic state,the saturated magnetic moment of the doped BaFe_(0.95)Co_(0.05)O_(3) increases by about 10%and reaches 3.64μB/f.u.Resistivity and specific heat measurements show that the ferromagnetic ordering favors metallic-like electrical transport behavior for BaFe_(0.95)Co_(0.05)O_(3).The present work indicates that Co-doping is an effective method to tune the magnetic and electric properties for the cubic perovskite phase of BaFeO_(3).

关键词： floating-zone single crystal high-pressure synthesis chemical doping magnetic and electrical properties

Recent progress in design of conductive polymers to improve the thermoelectric performance

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Chinese Physics B 2022年第2期31卷 22-32页

作者：徐真李慧陈立东 State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Organic semiconductors,especially polymer semiconductors,have attracted extensive attention as organic thermoelectric materials due to their capabilities for flexibility,low-cost fabrication,solution processability and low thermal conductivity.However,it is challenging to obtain high-performance organic thermoelectric materials because of the low intrinsic carrier concentration of organic semiconductors.The main method to control the carrier concentration of polymers is the chemical doping process by charge transfer between polymer and dopant.Therefore,the deep understanding of doping mechanisms from the point view of chemical structure has been highly desired to overcome the bottlenecks in polymeric thermoelectrics.In this contribution,we will briefly review the recently emerging progress for discovering the structure–property relationship of organic thermoelectric materials with high performance.Highlights include some achievements about doping strategies to effectively modulate the carrier concentration,the design rules of building blocks and side chains to enhance charge transport and improve the doping efficiency.Finally,we will give our viewpoints on the challenges and opportunities in the field of polymer thermoelectric materials.

关键词： conductive polymer organic thermoelectric material chemical doping side chain engineering

A three-dimensional polycyclic aromatic hydrocarbon based covalent organic framework doped with iodine for electrical conduction

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Chinese chemical Letters 2023年第4期34卷 601-604页

作者： Ruofan Li Guolong Xing Hui Li Shen Li Long Chen Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China Zhejiang Engineering Laboratory for Green Syntheses and Applications of Fluorine-Containing Specialty chemicals Institute of Advanced Fluorine-Containing MaterialsZhejiang Normal UniversityJinhua 321004China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012China

Covalent organic frameworks(COFs) are a class of crystalline porous organic materials with variable structures and fascinating properties. The intrinsic low conductivity impedes their widely application in optoelectronic. Iodine doping is an effective way to enhance the electrical conductivity of COFs. Here, a novel 3D imine COF with lvt topology is synthesized from two different pentacene derivatives with the same core in the form of structural complementarity. DDHP-COF is a highly crystalline material featuring high surface area of 1679 m^(2)/g and excellent thermal stability up to 490 ℃. Upon doping with iodine, the electrical conductivity can reach as high as 1.5×10^(-2)S/m which is significantly enhanced over 6 orders of magnitude compared with the pristine COF.

关键词： Three-dimensional Covalent organic frameworks Imine linkage chemical doping Electrical conduction

Tailoring of electromagnetic field localizations by twodimensional graphene nanostructures

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Light(Science & Applications) 2017年第1期6卷 497-504页

作者： Ze-Bo Zheng Jun-Tao Li Teng Ma Han-Lin Fang Wen-Cai Ren Jun Chen Jun-Cong She Yu Zhang Fei Liu Huan-Jun Chen Shao-Zhi Deng Ning-Sheng Xu State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologyGuangzhou 510275China State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Graphene has great potential for enhancing light−matter interactions in a two-dimensional regime due to surface plasmons with low loss and strong light confinement.Further utilization of graphene in nanophotonics relies on the precise control of light localization properties.Here,we demonstrate the tailoring of electromagnetic field localizations in the mid-infrared region by precisely shaping the graphene into nanostructures with different geometries.We generalize the phenomenological cavity model and employ nanoimaging techniques to quantitatively calculate and experimentally visualize the two-dimensional electromagnetic field distributions within the nanostructures,which indicate that the electromagnetic field can be shaped into specific patterns depending on the shapes and sizes of the nanostructures.Furthermore,we show that the light localization performance can be further improved by reducing the sizes of the nanostructures,where a lateral confinement of λ0/180 of the incidence light can be achieved.The electromagnetic field localizations within a nanostructure with a specific geometry can also be modulated by chemical doping.Our strategies can,in principle,be generalized to other two-dimensional materials,therefore providing new degrees of freedom for designing nanophotonic components capable of tailoring two-dimensional light confinement over a broad wavelength range.

关键词： chemical doping electromagnetic field localizations graphene graphene nanostructures graphene plasmons

Hydrothermal synthesis,structure and property of nano-BaTiO_3-based dielectric materials

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Science China Chemistry 2001年第6期44卷 657-662页

作者：丁士文王静秦江雷李希茂 Hebei University Baoding China

A series of Ba1-xSrxTi1-yZryO3 (0≤x≤0.5, 0≤y≤0.4) and Ba1-xZnxTi1-ySnyO3 (0≤x≤0.3, 0≤y≤0.3) solid solutions were synthesized by low-temperature/low-pressure hydrothermal method below 170℃, 0.8 MPa. XRD pattern and cell parameters-composition figures of these prepared powders demonstrated that they are completely miscible solid solutions based on BaTiO3. Furthermore, TEM showed that they have a shape of uniform, substantially spherical particles with an average particle size of 70 nm in diameter. The sintered ceramics of those powders doped by Sr2+ and Zr4+ or Zn2+ and Sn4+ have dielectric constant twelve times higher than and dielectric loss 1/6 those of pure BaTiO3 phase at room temperature.

关键词： hydrothermal synthesis BaTiO3 solid solutions chemical doping dielectric property.

Study of Graphdiyne-based Magnetic Materials

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chemical Research in Chinese Universities 2021年第6期37卷 1257-1267页

作者： LI Ru ZHANG Mingjia LI Xiaodong MA Xiaodi HUANG Changshui Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao266101P.R.China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049P.R.China

Carbon-based magnetic semiconductors are easy to be modified with low cost and low power consumption.While they can demonstrate robust long-range magnetic ordering and show great potential for application after introducing magnetic moments.Graphdiyne(GDY),as an allotrope of carbon,exhibits intrinsic semiconductor properties and paramagnetic properties due to its unique structure and the presence of sp carbon.To improve the magnetic properties of GDY and prepare excellent magnetic semiconductor materials,scientists have done a lot of related research work.The most direct and effective method to introduce magnetism is heteroatom doping.In this review,we have entirely described the latest GDY magnetism introduction methods,effects,and theoretical calculations,etc.doping methods include post-doping and molecular design doping.The doping elements have covered non-metallic elements(N,H,F,Cl,S),metallic elements(Fe),and functional groups.The magnetic properties of the modified GDY materials were studied by experimental analysis and theoretical calculations.This review provides a sufficient basis and direction for related researches.

关键词： Graphdiyne chemical doping Magnetic property Ferromagnetism semiconductor Spintronics