During the last decade, modern micro-electro-mechanical systems (MEMS) technology has been used to create cells that can act as catalytic nanoreactors and fit into the sample holders of transmission electron microscopes. These nanoreactors can maintain atmospheric or higher pressures inside the cells as they seal gases or liquids from the vacuum of the TEM column and can reach temperatures exceeding 1000 °C. This has led to a paradigm shift in electron microscopy, which facilitates the local characterization of structural and morphological changes of solid catalysts under working conditions. In this review, we outline the development of state-of-the-art nanoreactor setups that are commercially available and are currently applied to study catalytic reactions in situ or operando in gaseous or liquid environments. We also discuss challenges that are associated with the use of environmental cells. In catalysis studies, one of the major challenge is the interpretation of the results while considering the discrepancies in kinetics between MEMS based gas cells and fixed bed reactors, the interactions of the electron beam with the sample, as well as support effects. Finally, we critically analyze the general role of MEMS based nanoreactors in electron microscopy and catalysis communities and present possible future directions.

在过去的十年中，现代微机电系统（MEMS）技术已用于创建可充当催化纳米反应器并适合透射电子显微镜样品架的电池。这些纳米反应器可以从TEM柱的真空中密封气体或液体，并且可以维持超过1000°C的温度，从而在电池内部维持大气压或更高压力。这导致了电子显微镜的范式转变，这有助于在工作条件下对固体催化剂的结构和形态变化进行局部表征。在这篇综述中，我们概述了目前市场上最先进的纳米反应器装置的开发，这些装置目前用于研究原位或操作中的催化反应。在气体或液体环境中。我们还将讨论与使用环境电池相关的挑战。在催化研究中，主要挑战之一是在解释结果的同时要考虑基于MEMS的气室与固定床反应器之间的动力学差异，电子束与样品的相互作用以及支持作用。最后，我们批判性地分析了基于MEMS的纳米反应器在电子显微镜和催化领域的一般作用，并提出了可能的未来方向。