Metal Clusters Dispersed on Oxide Supports: Preparation Methods and Metal-Support Interactions

Heterogeneous metal catalysts nowadays adopt more well-defined and complex structures to enhance their utility in industrial catalysis. The metal-support interactions (MSI) play the key role in the structure-activity relationship of the metal catalysts, among which oxide supported metal clusters have greatly magnified MSI during nanocatalysis and exhibit plenty of potential in building the model of interfacial effects associated with MSI at atomic/molecular levels. As the MSI can be readily affected by the properties of both constituents in supported assemblies, at least one structural factor of the constituents has to be controlled so as to elucidate the specific interfacial effects. Accordingly, when the size of nanoclusters is controlled to high level of uniformity, the influence of oxide supports on the MSI can be uncovered and a mechanistic model of MSI in oxide supported catalysts can be established. Starting with the summary of the preparation techniques of size-controlled supported metal clusters, this review pays close attention to the variation and regulation of MSI in metal clusters supported by oxides with different reducibilities and conductivities, and proposes the specific mechanistic models of MSI on different supports.