Tuning the Molecular Structure and Reaction Mechanism of Olefin Metathesis by Model Bilayered Supported MoOx/AlOx/SiO2 Catalysts

The molecular structure and activity of supported MoOx olefin metathesis catalysts are heavily impacted by the choice of catalyst support. In this study, surface modification of the SiO2 support with AlOx and selective anchoring of the MoOx on the surface AlOx sites were used to tune the structure, activation, and reactivity of the resulting surface MoOx sites. Extensive in situ molecular characterization, chemical probe studies, and density functional theory (DFT) calculations reveal that the enhanced activity of the supported MoOx/AlOx/SiO2 catalyst over the MoOx/SiO2 catalyst is associated with more favorable activation and kinetics of surface MoOx anchored at AlOx sites.