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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 427-432页

作者： E.Spiecker L.Zhang H.M.Lu W.Jaeger L.Vescan MicroanalysisofMaterials FacultyofEngineeringChrisfian-Albrechts-UniversityKielKaiserstraβe224143KielGermany InstituteofThinFilmsandInterfaces ResearchCenterJiilichGmbH52425JiilichGermany

Shapes, dimensions, arrangements and the microstructure of self-assembled island s fabricated by low-pressure chemical vapour deposition (LPCVD) of Ge at 700℃ o nto Si(110) substrates have been investigated for different nominal Ge coverage by transmission electron microscopy (TEM) of plan-view and cross-section specime ns and have been compared with photoluminescence (PL) measurements of Si-capped layer samples. The transition from the 2-dimensional layer to the 3-dimensional island growth mode takes place for a Ge deposition of nominally less than 2 mono layers. Upon this transition, many coherent islands and few larger islands with extended defects are observed. The coherent islands possess a dome-like shape an d lateral sizes up to 130nm. Photoluminescence spectra show island-related peaks whose energy positions are shifted towards lower energy with higher Ge coverage .

关键词： Si-Ge heteroepitaxy surface transmission electron microscopy Nanostructure

transmission electron microscopy as a Powerful Tool for Investigating Lithium-ion Battery Materials

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Chinese Journal of Structural Chemistry 2019年第12期38卷 2015-2019页

作者： LIN Cong LI Jian-Yuan WANG Chong-Min PAN Feng School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055China Environmental Molecular Sciences Laboratory Pacific Northwest National LaboratoryRichlandWashington 99352USA

transmission electron microscopy(TEM) stands out as one of the most powerful tools for characterizing materials at multiple scales and dimensions. This unique technique has nowadays been widely employed in investigating the lithium-ion battery(LIB) materials. The present perspective paper focuses on several LIB related aspects that are recently revealed by using TEM. Finally, we present outlook on the future directions of TEM for LIB research and development.

关键词： transmission electron microscopy lithium-ion batteries structures properties

transmission electron microscopy Investigation of the Ar^+ Ion Irradiation Effect in Semiconductor GaAs

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 35-40页

作者： Yang Xiangxiu Wang Renhui Yan Heping Zhang Ze Wuhan Univ Wuhan China

Room temperature irradiation effect of GaAs compound semiconductor by 100 keV Ar+ ions has been systematically studied by means of transmission electron microscopy. The dose dependenceoof the Ar+ ion irradiation and room temperature annealing effects have been investigated. The experimental results show that the structure of GaAs transforms from perfect crystalline through weakly and severely damaged crystalline to amorphous states with the increase of the irradiation dose and the damaged states are changed during room temperature annealing.

关键词： GaAs irradiation effect transmission electron microscopy

transmission electron microscopy of organic-inorganic hybrid perovskites:myths and truths

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Science Bulletin 2020年第19期65卷 1643-1649,M0004页

作者： Shulin Chen Ying Zhang Jinjin Zhao Zhou Mi Jingmin Zhang Jian Cao Jicai Feng Guanglei Zhang Junlei Qi Jiangyu Li Peng Gao electron microscopy Laboratory School of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering School of Mechanical EngineeringShijiazhuang Tiedao UniversityShijiazhuang 050043China Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Collaborative Innovation Center of Quantum Matter Beijing 100871China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

Organic-inorganic hybrid perovskites(OIHPs)have attracted extensive research interest as a promising candidate for efficient and inexpensive solar *** electron microscopy(TEM)characterizations that can benefit the fundamental understanding and the degradation mechanism are widely used for these ***,their sensitivity to the electron beam illumination and hence structural instabilities usually prevent us from obtaining the intrinsic information or even lead to significant ***,we systematically investigate the structural degradation behaviors under different experimental factors to reveal the optimized conditions for TEM characterizations of OIHPs by using low-dose electron diffraction and imaging *** find that a low temperature(-180°C)does not slow down the beam damage but instead induces a rapid amorphization for ***,a less severe damage is observed at a higher accelerating *** beam-sensitivity is found to be facetdependent that a(100)exposed CH3NH3PbI3(MAPbI3)surface is more stable than a(001)*** these guidance,we successfully acquire the atomic structure of pristine MAPbI3 and identify the characterization window that is very *** findings are helpful to guide future electron microscopy characterizations of these beam-sensitive materials,which are also useful for finding strategies to improve the stability and performance of the perovskite solar cells.

关键词： Organic-inorganic hybrid perovskites transmission electron microscopy Beam damage mechanism Atomic structure CH3NH3PbI3 Facet dependency

Characterization of local chemical ordering and deformation behavior in high entropy alloys by transmission electron microscopy

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 877-886页

作者： Qiuhong Liu Qing Du Xiaobin Zhang Yuan Wu Andrey A.Rempel Xiangyang Peng Xiongjun Liu Hui Wang Wenli Song Zhaoping Lü Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences Ekaterinburg 620016Russia China Nuclear Power Technology Research Institute Co.Ltd. Shenzhen 518000China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China

Short-range ordering(SRO)is one of the most important structural features of high entropy alloys(HEAs).However,the chemical and structural analyses of SROs are very difficult due to their small size,complexed compositions,and varied *** electron microscopy(TEM)as well as its aberration correction techniques are powerful for characterizing SROs in these compositionally complex *** this short communication,we summarized recent progresses regarding characterization of SROs using TEM in the field of *** using advanced TEM techniques,not only the existence of SROs was confirmed,but also the effect of SROs on the deformation mechanism was ***,the perspective related to application of TEM techniques in HEAs are also discussed.

关键词： high entropy alloys transmission electron microscopy short-range ordering deformation mechanisms

Unravelling the metal borides evolution in the transient liquid phase bonding of Ni-based alloys via high-throughput transmission electron microscopy and first-principles thermo-kinetic calculations

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Journal of Materials Science & Technology 2021年第26期85卷 118-128页

作者： Kewu Bai Ming Lin Institute of High Performance Computing Agency for ScienceTechnology and ResearchFusionopolis Way#16-16 ConnexisSingapore 138632Singapore Institute of Materials Research and Engineering(IMRE) Fusionopolis WayInnovis#08-03Singapore 138634Singapore

The understanding of temperature and time-dependent metal borides precipitation/dissolution is crucial for the design of the transient liquid phase(TLP)bonding process of Ni-based *** however remains elusive despite substantial research efforts for many years mainly owing to the uncertainty on the precipitated metal borides and the complex thermo-kinetics in the *** this paper,we have unambiguously constructed the micro/nano scale map of the precipitated metal borides in the TLP bonded Ni-based Inconel 718 superalloy via a high-throughput transmission electron microscopy(TEM)*** types of metal borides were found to precipitate in the diffusion affected zone(DAZ)when the isothermal solidification is *** are the M_(5)B_(3)with stacking faults,Ti-rich M_(3)B4,and Nb-rich M_(3)B4 at the grain boundaries as well as single-crystalline M_(5)B_(3)and M_(3)B2 inside the ***,the crystal structure of the faulted M_(5)B_(3)was rationalized by a hybrid modelling approach integrating firstprinciples calculation and TEM *** sublattice model,with the optimized thermodynamic model parameters,was used to reproduce the metal borides precipitation map in the TLP process using DICTRA *** with multiscale simulation and experimental data,the present work built a modified thermo-kinetic model,which enables the design of the TLP bonding process of Ni-based alloys that often involves complicated time-tempe rature schedules and the precipitation/dissolution of a variety of diffe rent *** strategy can be applied to the design of the brazing process of other alloys or hybrid materials such as ceramics and metal.

关键词： Ni-based superalloy transmission electron microscopy Transient liquid bonding Precipitation Kinetics

Tracking lithiation with transmission electron microscopy

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Science China Chemistry 2024年第1期67卷 291-311页

作者： Xincheng Lei Jianxiong Zhao Jiayi Wang Dong Su Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China South China Academy of Advanced Optoelectronics&International Academy of Optoelectronics at Zhaoqing South China Normal UniversityGuangzhou 510006China

Li-ion batteries(LIBs)have dominated energy-storage techniques for portable electronic devices and electric cars,and are expanding their territory into the large-scale energy *** energy storage of LIBs is realized by the reversible shuttle of lithium ions between *** is essential to track the lithium diffusion and obtain a profound insight into the lithiation mechanism during the work cycle of *** electron microscopy(TEM)is a powerful tool for the structural characterization,which can provide the information about the lithiation at the atomic *** this review,we summarize the research frontiers of TEM applications on *** introduce the techniques for the direct observation of Li species in LIB-related ***,the application of cryo-TEM is ***,in-situ TEM technique is further discussed since it shows great advantages in studying the dynamical structure changes of *** perspectives and strategies in this review offer feasible guidance for researchers to further improve the performance of LIBs.

关键词： lithium-ion battery electrode materials transmission electron microscopy cryo-TEM in-situ TEM

A transmission electron microscopy Study of Plate Martensite Formation in High-carbon Low Alloy Steels

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Journal of Materials Science & Technology 2013年第4期29卷 373-379页

作者： Albin Stormvinter Peter Hedstrm Annika Borgenstam Department of Materials Science and Engineering School of Industrial Engineering and ManagementKTH Royal Institute of TechnologySE-100 44 StockholmSweden

The martensitic microstructures in two high-carbon low alloy steels have been investigated by classical and automated crystallographic analysis under a transmission electron microscope. It is found that the martensitic substructure changes from consisting mostly of transformation twins for 1.20 mass% carbon （C） steel to both transformation twins and planar defects on {101}M for 1.67 mass% C steel. In the 1.67 mass% C steel it is further found that small martensite units have a rather homogeneous substructure, while large martensite units are more inhomogeneous. In addition, the martensite units in both steels are frequently found to be of zigzag patterns and have distinct crystallographic relationships with neighboring martensite units, e.g. kink or wedge couplings. Based on the present findings the development of martensite in high-carbon low alloy steels is discussed and a schematic of the martensite formation is presented. Moreover, whether the schematic view can be applied to plate martensite formation in general, is discussed.

关键词： transmission electron microscopy High-carbon low alloy steel Plate martensite

Probing the Nucleation and Growth Kinetics of Bismuth Nanoparticles via In-situ transmission electron microscopy

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 877-887页

作者：王浪李超凡 RAN Maojin YUAN Manman 胡执一 LI Yu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Nanostructure Research Centre(NRC) Wuhan University of TechnologyWuhan 430070China Institute of Chemistry Henan Academy of SciencesZhengzhou 450002China Henan Academy of Sciences Zhengzhou 450046China

The nucleation and growth mechanism of nanoparticles is an important theory,which can guide the preparation of ***,it is still lacking in direct observation on the details of the evolution of intermediate state structure during nucleation and *** this work,the evolution process of bismuth nanoparticles induced by electron beam was revealed by in-situ transmission electron microscopy(TEM)at atomic *** experimental results demonstrate that the size,stable surface and crystallographic defect have important influences on the growth of Bi *** non-classical growth paths including single crystal growth and polycrystalline combined growth,as well as,corresponding layer-by-layer growth mechanism along{012}stable crystal plane of Bi nanoparticles with dodecahedron structure were revealed by in-situ TEM *** results provide important guidance and a new approach for in-depth understanding of the nucleation and growth kinetics of nanoparticles.

关键词： bismuth nanoparticles crystal growth transmission electron microscopy in-situ electron microscopy

Misfit-layered compound PbTiS_3 with incommensurate modulation:transmission electron microscopy analysis and transport properties

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Chinese Physics B 2013年第11期22卷 423-426页

作者：沈希程丹赵豪飞姚湲刘晓旸禹日成 Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University

The microstructural characteristic of the misfit-layered compound PbTiS3 has been studied with transmission electron microscopy. All the incommensurate modulation-induced satellite spots and main diffraction spots of basic sublattices can be indexed systematically with a superspace group method. Finally, the relationship between the electronic transport properties and the crystal structure is discussed.

关键词： incommensurate modulation misfit-layered sulfide transmission electron microscopy