Environmental Scanning Transmission Electron Microscopy enables more realistic catalyst reaction studies
Heterogeneous gas-solid catalyst reactions occur on the atomic scale and there is increasing evidence single atoms and very small clusters can act as primary active sites in chemical reactions. When studying the reactions taking place at the catalyst surface, scientists usually have to look into idealized reaction systems under idealized conditions rather than examining the reality of an industrial catalytic process, which may be inhomogeneous samples at high temperatures and pressures. Structural features in inhomogeneous samples, such as heterogeneous industrial catalysts consisting, for example, of nano-particulate metals and high surface-area oxide supports, can be identified by modern high resolution microscopy techniques, especially by transmission electron microscopy (TEM). Yet, these studies still had to be carried out, very unrealistically, under high vacuum conditions.