Understanding how catalysts work during chemical reactions is crucial when developing efficient catalytic materials. The dynamic processes involved are extremely sensitive to changes in pressure, gas environment and temperature. Hence, there is a need for spatially resolved operando techniques to investigate catalysts under working conditions and over time. The use of dedicated operando techniques with added detection of catalytic conversion presents a unique opportunity to study the mechanisms underlying the catalytic reactions systematically. Herein, we report on the detailed setup and technical capabilities of a modular, homebuilt gas feed system directly coupled to a quadrupole mass spectrometer, which allows for operando transmission electron microscopy (TEM) studies of heterogeneous catalysts. The setup is compatible with conventional, commercially available gas cell TEM holders, making it widely accessible and reproducible by the community. In addition, the operando functionality of the setup was tested using CO oxidation over Pt nanoparticles.

中文翻译：

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用于工作中催化剂的 Operando TEM 的多功能自制气体进料和分析系统

在开发高效的催化材料时，了解催化剂在化学反应中的工作原理至关重要。所涉及的动态过程对压力、气体环境和温度的变化极为敏感。因此，需要空间分辨操作在工作条件下和随时间推移研究催化剂的技术。使用专用操作增加催化转化检测的技术为系统地研究催化反应的机制提供了独特的机会。在这里，我们报告了直接耦合到四极质谱仪的模块化、自制气体进料系统的详细设置和技术能力，该系统允许操作非均相催化剂的透射电子显微镜（TEM）研究。该设置与传统的市售气室 TEM 支架兼容，使其可被社区广泛使用和复制。除此之外操作使用 Pt 纳米粒子上的 CO 氧化测试了该装置的功能。