High-resolution electron microscopy for heterogeneous catalysis research

doi:10.1088/1674-1056/27/5/056804

摘要/Abstract

摘要： Heterogeneous catalysts are the most important catalysts in industrial reactions. Nanocatalysts, with size ranging from hundreds of nanometers to the atomic scale, possess activities that are closely connected to their structural characteristics such as particle size, surface morphology, and three-dimensional topography. Recently, the development of advanced analytical transmission electron microscopy (TEM) techniques, especially quantitative high-angle annular dark-field (HAADF) imaging and high-energy resolution spectroscopy analysis in scanning transmission electron microscopy (STEM) at the atomic scale, strengthens the power of (S)TEM in analyzing the structural/chemical information of heterogeneous catalysts. Three-dimensional reconstruction from two-dimensional projected images and the real-time recording of structural evolution during catalytic reactions using in-situ (S)TEM methods further broaden the scope of (S)TEM observation. The atomic-scale structural information obtained from high-resolution (S)TEM has proven to be of significance for better understanding and designing of new catalysts with enhanced performance.

关键词: atomic resolution, electron microscopy, three-dimensional (3D) reconstruction, in-situ, heterogeneous catalysts

Abstract: Heterogeneous catalysts are the most important catalysts in industrial reactions. Nanocatalysts, with size ranging from hundreds of nanometers to the atomic scale, possess activities that are closely connected to their structural characteristics such as particle size, surface morphology, and three-dimensional topography. Recently, the development of advanced analytical transmission electron microscopy (TEM) techniques, especially quantitative high-angle annular dark-field (HAADF) imaging and high-energy resolution spectroscopy analysis in scanning transmission electron microscopy (STEM) at the atomic scale, strengthens the power of (S)TEM in analyzing the structural/chemical information of heterogeneous catalysts. Three-dimensional reconstruction from two-dimensional projected images and the real-time recording of structural evolution during catalytic reactions using in-situ (S)TEM methods further broaden the scope of (S)TEM observation. The atomic-scale structural information obtained from high-resolution (S)TEM has proven to be of significance for better understanding and designing of new catalysts with enhanced performance.

Key words: atomic resolution, electron microscopy, three-dimensional (3D) reconstruction, in-situ, heterogeneous catalysts

中图分类号: (High-resolution transmission electron microscopy (HRTEM))

68.37.Og

79.20.Uv (Electron energy loss spectroscopy) 82.65.+r (Surface and interface chemistry; heterogeneous catalysis at surfaces)

朱勇, 许名权, 周武. High-resolution electron microscopy for heterogeneous catalysis research[J]. 中国物理B, 2018, 27(5): 56804-056804.

Yong Zhu(朱勇), Mingquan Xu(许名权), Wu Zhou(周武). High-resolution electron microscopy for heterogeneous catalysis research[J]. Chin. Phys. B, 2018, 27(5): 56804-056804.

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