Overcoming Limitations in the Strong Interaction between Pt and Irreducible SiO2 Enables Efficient and Selective Hydrogenation of Anthracene.

Abstract

Interactions between metals and oxide supports are crucial in determining catalytic activity, selectivity, and stability. For reducible oxide supported noble metals, a strong metal-support interaction (SMSI) has been widely recognized. Herein we report the intermediate selectivity and stability over an irreducible SiO2 supported Pt catalyst in the hydrogenation of anthracene that are significantly boosted due to the SMSI-induced formation of intermetallic Pt silicide and Pt-SiO2 interface. The limitation in the strong interaction between Pt nanoparticles and irreducible SiO2 has been breached by combining the strong electrostatic adsorption method and following the high temperature reduction strategy. Due to the isolated Pt active sites by Si atoms, the activated H species produced over the Pt2Si/SiO2 catalyst with an initial catalytic activity of 2.49 μmol/(m2/g)/h as well as TOF of 0.95 s-1 preferentially transfer to the outer ring of anthracene to 87% yield of symmetric octahydroanthracene (sym-OHA) by subsequent hydrogenation. In addition, the Pt2Si/SiO2 catalyst presents an excellent stability after five cycles, which can be attributed to the fact that intermetallic Pt2Si nanoparticles are anchored firmly onto the surface of the SiO2 support. The discovery contributes to broaden the horizons on the SMSI effect in the irreducible oxide supported metal particle catalysts and provides guidance to design the metal-SiO2 interface and tune the surface chemical properties in diverse application conditions.