Structure Sensitivity of Au‐TiO<sub>2</sub> Strong Metal–Support Interactions
Yunshang Zhang, Jin‐Xun Liu, Kun Qian, Aiping Jia, Wei‐Xue Li, Lei Shi, Jun Hu, Junfa Zhu, Weixin Huang
Abstract
Abstract Strong metal–support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au‐TiO 2 SMSI of Au/TiO 2 catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO 2 facets. Au NPs of ca. 5 nm are more facile undergo Au‐TiO 2 SMSI than those of ca. 2 nm, while TiO 2 {001} and {100} facets are more facile than TiO 2 {101} facets. The resulting capsulating TiO 2− x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au‐to‐TiO 2− x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO 2− x overlayers and TiO 2− x ‐Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low‐temperature CO oxidation than the starting Au‐TiO 2 interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis.