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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

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 storage.The energy storage of LIBs is realized by the reversible shuttle of lithium ions between electrodes.It is essential to track the lithium diffusion and obtain a profound insight into the lithiation mechanism during the work cycle of LIBs.transmission electron microscopy(TEM)is a powerful tool for the structural characterization,which can provide the information about the lithiation at the atomic scale.In this review,we summarize the research frontiers of TEM applications on LIBs.We introduce the techniques for the direct observation of Li species in LIB-related materials.Especially,the application of cryo-TEM is highlighted.Moreover,in-situ TEM technique is further discussed since it shows great advantages in studying the dynamical structure changes of LIBs.The 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

transmission electron microscopy INVESTIGATIONS OF LOW-PRESSURE CVD GROWTH AND STRAIN RELAXATION OF Ge ISLANDS ON Si(110)

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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

Automatic Measurement of Silicon Lattice Spacings in High-Resolution transmission electron microscopy Images Through 2D Discrete Fourier Transform and Inverse Discrete Fourier Transform

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Nanomanufacturing and Metrology 2022年第2期5卷 119-126页

作者： Fang Wang Yushu Shi Shu Zhang Xixi Yu Wei Li National Institute of Metrology Beijing100029China Shenzhen Institute for Technology Innovation National Institute of MetrologyShenzhen518038China

Line width(i.e.,critical dimension,CD)is a crucial parameter in integrated circuits.To accurately control the CD in manufacturing,a reasonable CD measurement algorithm is required.We develop an automatic and accurate method based on a two-dimensional discrete Fourier transform for measuring the lattice spacings from high-resolution transmission electron microscopy images.Through the two-dimensional inverse discrete Fourier transform of the central spot and a pair of symmetrical diffraction spots,an image containing only a set of lattice spacings is obtained.Then,the pixel span of the lattice spacing is calculated through the centre of gravity method.Finally,we estimate the standard CD value according to the half-intensity method.The silicon crystal lattice constant guarantees the accuracy and traceability of the CD value.Through experiments,we demonstrate the efficiency of the proposed method,which can be conveniently applied to accurately measure CDs in practical applications.

关键词： transmission electron microscopy Line width Crystal lattice constant Traceability

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 alloys.It 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 process.In 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)analysis.Five types of metal borides were found to precipitate in the diffusion affected zone(DAZ)when the isothermal solidification is completed.They 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 grains.Notably,the crystal structure of the faulted M_(5)B_(3)was rationalized by a hybrid modelling approach integrating firstprinciples calculation and TEM experiments.The sublattice model,with the optimized thermodynamic model parameters,was used to reproduce the metal borides precipitation map in the TLP process using DICTRA software.Coupling 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 phases.The 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

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 locations.transmission electron microscopy(TEM)as well as its aberration correction techniques are powerful for characterizing SROs in these compositionally complex alloys.In this short communication,we summarized recent progresses regarding characterization of SROs using TEM in the field of HEAs.By using advanced TEM techniques,not only the existence of SROs was confirmed,but also the effect of SROs on the deformation mechanism was clarified.Moreover,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

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

Recent progress on advanced transmission electron microscopy characterization for halide perovskite semiconductors

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Journal of Semiconductors 2022年第4期43卷 67-81页

作者： Xiaomei Wu Xiaoxing Ke Manling Sui Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China

Halide perovskites are strategically important in the field of energy materials. Along with the rapid development of the materials and related devices, there is an urgent need to understand the structure–property relationship from nanoscale to atomic scale. Much effort has been made in the past few years to overcome the difficulty of imaging limited by electron dose,and to further extend the investigation towards operando conditions. This review is dedicated to recent studies of advanced transmission electron microscopy(TEM) characterizations for halide perovskites. The irradiation damage caused by the interaction of electron beams and perovskites under conventional imaging conditions are first summarized and discussed. Low-dose TEM is then discussed, including electron diffraction and emerging techniques for high-resolution TEM(HRTEM) imaging. Atomic-resolution imaging, defects identification and chemical mapping on halide perovskites are reviewed. Cryo-TEM for halide perovskites is discussed, since it can readily suppress irradiation damage and has been rapidly developed in the past few years. Finally, the applications of in-situ TEM in the degradation study of perovskites under environmental conditions such as heating,biasing, light illumination and humidity are reviewed. More applications of emerging TEM characterizations are foreseen in the coming future, unveiling the structural origin of halide perovskite’s unique properties and degradation mechanism under operando conditions, so to assist the design of a more efficient and robust energy material.

关键词： organic–inorganic hybrid perovskite solar cell materials energy materials scanning electron microscopy transmission electron microscopy irradiation damage

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