The Principles Behind Different Forms of Strong Metal‐Support Interaction in Heterogeneous Catalysts

Strong metal‐support interaction (SMSI) is a special form of interaction between metal species and supports in heterogeneous catalysts, and manifests as various types of geometric structure changes. These SMSI behaviors serve as effective strategies to precisely regulate the surface and interface structures of supported metals, and hence has stimulated extensive research interest on the construction and regulation of SMSI. While the nature of SMSI has long been regarded as the strong interfacial metallic bonds between the supported metals and the metal cations in supports, it remains elusive why such a universal principle results in diverse structural changes in different material systems. In this perspective, it is explored and summarized the SMSI behaviors across different material systems, aiming to provide a systematic and unified framework for understanding SMSI. It is suggested that the direct reduction of surface energy and the increase of entropy is the thermodynamic driving force of SMSI, and the kinetic factors, i.e. the diffusion rate of metal atoms, determine the specific form of SMSI. This perspective would provide deeper and more systematic insights into SMSI behaviors and is instrumental to the precise regulation of the surface and interface structures of supported metal catalysts.