Thomas John Meurig
Department of Materials Science and Metallurgy , University of Cambridge , 27 Charles Babbage Road, Cambridge CB3 0FS , UK.
Proc Math Phys Eng Sci. 2017 Jan;473(2197):20160714. doi: 10.1098/rspa.2016.0714.
Electron microscopy (EM) is arguably the single most powerful method of characterizing heterogeneous catalysts. Irrespective of whether they are bulk and multiphasic, or monophasic and monocrystalline, or nanocluster and even single-atom and on a support, their structures in atomic detail can be visualized in two or three dimensions, thanks to high-resolution instruments, with sub-Ångstrom spatial resolutions. Their topography, tomography, phase-purity, composition, as well as the bonding, and valence-states of their constituent atoms and ions and, in favourable circumstances, the short-range and long-range atomic order and dynamics of the catalytically active sites, can all be retrieved by the panoply of variants of modern EM. The latter embrace electron crystallography, rotation and precession electron diffraction, X-ray emission and high-resolution electron energy-loss spectra (EELS). Aberration-corrected (AC) transmission (TEM) and scanning transmission electron microscopy (STEM) have led to a revolution in structure determination. Environmental EM is already playing an increasing role in catalyst characterization, and new advances, involving special cells for the study of solid catalysts in contact with liquid reactants, have recently been deployed.
电子显微镜（EM）可以说是表征多相催化剂最强大的单一方法。无论它们是块状多相的、单相单晶的、纳米团簇甚至是单原子且负载在载体上的，借助具有亚埃空间分辨率的高分辨率仪器，它们的原子细节结构都能在二维或三维中可视化。它们的形貌、断层扫描、相纯度、组成，以及其组成原子和离子的键合、价态，在有利情况下，催化活性位点的短程和长程原子有序性及动力学，都可以通过现代电子显微镜的各种变体技术来获取。后者包括电子晶体学、旋转和进动电子衍射、X射线发射以及高分辨率电子能量损失谱（EELS）。像差校正（AC）透射电子显微镜（TEM）和扫描透射电子显微镜（STEM）已经引发了结构测定方面的一场革命。环境电子显微镜在催化剂表征中已经发挥着越来越重要的作用，并且最近已经采用了涉及用于研究与液体反应物接触的固体催化剂的特殊样品池等新进展。
