(Invited) Engineering Au/TiO2 Interface for Electron-Driven Heterogeneous Catalysis

Abstract

Interfacial electronic properties of Metal/oxide have been extensively studied due to its importance for heterogeneous catalysis, however, to date, the exact role of interfacial atomic structures in governing catalytic processes still remains elusive. Herein, we demonstrate how the manipulation of atomic structures at the Au/TiO2 interface significantly alters the interfacial electron distribution and prompts O2 activation. It is discovered that at the defect-free Au/TiO2 interface, electrons transfer from Ti3+ species into Au nanoparticles (NPs) and further migrate into adsorbed perimeter O2 molecules (i.e., in the form of Au-O-O-Ti), facilitating O2 activation and leading to a 34 times higher CO oxidation activity than that on the oxygen vacancy (V o)-rich interface, at which electrons from Ti centers are trapped by interfacial V o ­on TiO2 and hardly interact with perimeter O2 molecules. Collectively, our results establish an atomic-level description of the underlying mechanism regulating the atomic structure at metal/oxide interfaces for optimizing heterogeneous catalysis.