Facet-dependent anchoring of gold nanoparticles on TiO2 for CO oxidation

The interfacial perimeter of gold nanocatalysts is popularly viewed as the active sites for a number of chemical reactions, while the geometrical structure of the interface at atomic scale is less known. Here, TiO2-nanosheets and nanospindles were adapted to accommodate Au particles (∼2.2 nm), forming Au-TiO2{001} and Au-TiO2{101} interfaces. Upon calcination at 623 K in air, HAADF-STEM images evidenced that the Au particles on TiO2{101} enlarged to 3.1 nm and these on TiO2{001} remained unchanged, suggesting the stronger metal-support interaction on TiO2{001}. Au/TiO2{001} was more active for CO oxidation than Au/TiO2{101} system.