Recent Advances in Regulating Metal-Silica Interaction for Boosting Heterogeneous Catalytic Performance.

Heterogeneous catalysts are extensively utilized in the modern chemical industry, with catalytic processes primarily occurring on the surfaces of nanocrystals. Construction of an optimum surface/interface is of significant importance in regulating the catalytic performance. Strong metal-support interactions (SMSI) have been proven to be an efficient strategy to modulate the electronic and geometric properties of the supported nanocrystals by forming a thin amorphous coating layer and a new metal bond. The classical SMSI typically occurred on reducible metal oxides (TiO2, CeO2, Nb2O5, and Fe2O3) under a reduction environment. Nevertheless, the SMSI effect could be successfully engineered for the inert oxides (Al2O3, MgO, and SiO2) under much more severe conditions owing to the inertness of hard-to-reduce oxides compared with reducible oxides. Over the past few decades, it has been observed that the amorphous encapsulation layer could be induced under much higher temperatures, as well as the formation of a metal-Si bond, which significantly promotes various catalysis. In this review, we focus on the construction of metal-silica interaction and the dynamics of structure evolution of the metal crystals under certain reaction conditions, while highlighting their unique features in heterogeneous catalytic processes.