The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous a...The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous advancement in computational technology,specialized software and programs have emerged as potent facilitators across the entirety of electron microscopy characterization process.Utilizing advanced image processing algorithms promotes the rectification of image distortions,concurrently elevating the overall image quality to superior standards.Extracting high-resolution,pixel-level discrete information and converting it into atomic-scale,followed by performing statistical calculations on the physical matters of interest through quantitative analysis,represent an effective strategy to maximize the value of electron microscope images.The efficacious utilization of quantitative analysis of electron microscope images has become a progressively prominent consideration for materials scientists and electron microscopy researchers.This article offers a concise overview of the pivotal procedures in quantitative analysis and summarizes the computational methodologies involved from three perspectives:contrast,lattice and strain,as well as atomic displacements and polarization.It further elaborates on practical applications of these methods in electronic functional materials,notably in piezoelectrics/ferroelectrics and thermoelectrics.It emphasizes the indispensable role of quantitative analysis in fundamental theoretical research,elucidating the structure–property correlations in high-performance systems,and guiding synthesis strategies.展开更多
Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mec...Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.展开更多
基金Project supported by the financial support from the National Key R&D Program of China(Grant No.2021YFB3201100)the National Natural Science Foundation of China(Grant No.52172128)the Top Young Talents Programme of Xi’an Jiaotong University.
文摘The stable sub-angstrom resolution of the aberration-corrected scanning transmission electron microscope(ACSTEM)makes it an advanced and practical characterization technique for all materials.Owing to the prosperous advancement in computational technology,specialized software and programs have emerged as potent facilitators across the entirety of electron microscopy characterization process.Utilizing advanced image processing algorithms promotes the rectification of image distortions,concurrently elevating the overall image quality to superior standards.Extracting high-resolution,pixel-level discrete information and converting it into atomic-scale,followed by performing statistical calculations on the physical matters of interest through quantitative analysis,represent an effective strategy to maximize the value of electron microscope images.The efficacious utilization of quantitative analysis of electron microscope images has become a progressively prominent consideration for materials scientists and electron microscopy researchers.This article offers a concise overview of the pivotal procedures in quantitative analysis and summarizes the computational methodologies involved from three perspectives:contrast,lattice and strain,as well as atomic displacements and polarization.It further elaborates on practical applications of these methods in electronic functional materials,notably in piezoelectrics/ferroelectrics and thermoelectrics.It emphasizes the indispensable role of quantitative analysis in fundamental theoretical research,elucidating the structure–property correlations in high-performance systems,and guiding synthesis strategies.
基金supported by the National Natural Science Foundation of China(NSFC)under grant No.51902155the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Revealing the epitaxial growth mechanism and the interfacial coupling effect between oxide films will help to build a“structure-property”bridge for the design of microelectronic devices.Here,the epitaxial growth mechanism and the interfacial coupling in Bi_(0.5)Na_(0.5)TiO_(3)/SrTiO_(3)(BNT/STO)heterointerfaces are investigated by the aberration-corrected scanning transmission electron microscopy,which is synthesized by a hydrothermal method.The results illustrate that 4 mol/L NaOH leads to not only the epitaxial growth of the BNT film but also the mutual diffusion of elements.The uneven distribution of local elements in BNT films is observed and confirmed to impact the cation displacements of B-site and lattice distortion.However,the overall trend of B-site cation displacement at the BNT/STO heterointerfaces is dominated by the interfacial strain.Additionally,the oxygen octahedral tilt exhibits continuous tilt patterns of a^(0)a^(0)a^(0)-a−b^(0)c−-a^(0)a^(0)c−-a^(0)b−c−-a−b−c−from the substrate to BNT film due to the constraint of the substrate and presents a strong correlation with cation displacement.These results are helpful to understand the underlying atomic structures and physical properties of BNT epitaxial thin films.
