Assessing the Effect of the Electron‐Beam Irradiation on Pd/Ga2O3 Catalyst under Ambient Pressure

Abstract

AbstractIntroducing atmosphere in transmission electron microscope enables to directly observe the structural features of catalyst under working conditions. It offers the possibility to study the microstructural evolution and correlate real structures with catalytic properties at nano‐ or atomic‐scale during catalysis. However, the damages to catalyst derived from the high energy electron‐beam irradiation cannot be ignored and may lead to ambiguous conclusions, as the interaction between reactive gas molecules and active structures is only desired. Herein, the α‐Ga2O3 supported Pd catalyst was selected as a model to evaluate the potential effect of electron‐beam on the surface and interface structures, which directly affect the catalytic performance, at varied atmospheres, elevated temperatures and increased electron dose rate in ambient pressure. The results indicate that the supported Pd nanoparticles could be encapsulated by GaOx layer when the imaging electron dose rate is higher than 100 e/Å2s under reduction and oxidizing atmosphere. Either increasing the electron dose rate or elevating the temperature exacerbates the irradiation damage to α‐Ga2O3 support. This work was expected to evaluate the effect of electron dose rate to supported catalysts under chemical environments, and provide guidance for the investigation of in‐situ transmission electron microscopy under ambient pressure.