In situ observation of catalyst nanoparticle sintering resistance on oxide supports via gas phase transmission electron microscopy

Abstract

Oxide-supported metal catalysts are essential components in industrial processes for catalytic conversion. However, the performance of these catalysts is often compromised in high temperature reaction environments due to sintering effects. Currently, a number of studies are underway with the objective of improving the metal support interaction (MSI) effect in order to enhance sintering resistance by surface modification of the oxide support, including the formation of inhomogeneous defects on the oxide support, the addition of a rare earth element, the use of different facets, encapsulation, and other techniques. The recent developments in in situ gas phase transmission electron microscopy (TEM) have enabled direct observation of the sintering process of NPs in real time. This capability further allows to verify the efficacy of the methods used to tailor the support surface and contributes effectively to improving sintering resistance. Here, we review a few selected studies on how in situ gas phase TEM has been used to prevent the sintering of catalyst NPs on oxide supports.