Specific Metal-Support Interactions between Nanoparticle Layers for Catalysts with Enhanced Methanol Oxidation Activity

Abstract

Oxide supports often play a critical role in metal-supported catalysts owing to their charge transfer phenomena that can alter catalytic performance. Herein, in place of conventional bulk oxide supports, monodisperse oxide nanoparticles (NPs) were exploited as supports for Pt catalysts. Depending on the type of oxide NP, Pt/oxide layered catalysts exhibited dramatic changes in the catalytic activity and selectivity for methanol oxidation. While Pt NPs deposited on MnO, Fe3O4, Co3O4, Cu2O, and ZnO NPs had comparable turnover frequencies to that of the pure Pt NP catalyst, Pt deposited TiO2 NPs changed the reaction rate significantly, with preferential selectivity observed toward partial oxidation products. Facet-specific interactions between Pt and TiO2 NPs were demonstrated by density functional theory calculations and catalytic reactions using shape-controlled TiO2 NPs. When Pt NPs were attached to spherical and rhombic TiO2 NPs with abundant (001) surfaces, methanol conversion was enhanced 10-fold owing to strong charge transfer from TiO2 to Pt.