基于透射电子显微镜的沸石分子筛结构研究进展

Progress of Zeolite Structural Analysis Based on Transmission Electron Microscopy

透射电子显微镜是解析沸石分子筛新结构、分析结构缺陷和研究活性位点等的有力工具.应用于分子筛研究的透射电子显微术总体上可以分为图像法和衍射法,包括透射电子显微镜和扫描透射电子显微图像、选区电子衍射和三维电子衍射,通常结合其中的几种方法进行分析.近年来,随着电子显微镜硬件性能的不断提升,特别是球差矫正器的广泛应用及各种适用于分子筛等电子束敏感材料的探测器和图像处理技术的不断革新,在原子尺度观察分子筛的结构已成为可能.此外,利用原位电子显微镜技术研究分子筛的生长和催化反应机理也在逐步展开.本文按电子显微镜方法分类,综述了近些年基于电子显微镜的分子筛研究,包括新结构解析、手性确认和金属负载等的最新进展.

Transmission electron microscope has become a powerful tool to solve new zeolite structures,ana⁃lyze structural defects and study active sites.It has two main functions,imaging and diffraction,including transmission/scanning transmission electron microscopy imaging,selected-area electron diffraction and threedimensional electron diffraction.Multiple methods were usually combined for a thorough analysis.In recent years,there are breakthrough improvements on hardware of electron microscopes,especially the welldeveloped spherical aberration correctors and a variety of sensitive detectors,as well as developments of image processing methods.As a result,atomic level imaging of beam sensitive materials such as zeolites has been achievable.Moreover,in situ electron microscopy study of zeolite is also on the way,for a better understanding of zeolites growth and catalytic reaction.In this review we focus on the recent research progresses of zeolites studied by electron microscopy,including new structure analysis,handedness determination,metal@zeolites and so on.