In situ TEM Investigations of Catalysis Dynamics in Service Conditions

In this dissertation, we studied the behavior of nanoscale materials exposed to liquid, gas, and high temperature environments. This study was enabled by the utilization of in situ transmission electron microscopy (TEM) for the study of nanoscale reactions. We performed our in situ TEM evaluation using silicon nitride (SiN)-membrane gas cells, SiN-membranes with resistive Joule heating, and SiN-membrane liquid cells. Specifically, key insights are obtained for synthesis of two-dimensional (2D) heterostructures, degradation mechanisms of 2D-supported heterogeneous catalysts under service conditions, and behavior of high-entropy alloy materials in redox gaseous environments.