Interplay between invasive single atom Pt and native oxygen vacancy in rutile TiO2(110) surface: A theoretical study

Oxygen vacancy (O v ) as well as O v migration in metal oxide are of great importance in structural evolution of active center in single-atom catalysts (SACs). Here, the interplay between invasive single Pt atom and native O v in SA-Pt/rutile TiO 2 (110) surface, as well as their synergetic effect on water dissociation are investigated by density functional theory (DFT) calculations. We show that importing Pt atom as Pt-ads, Pt 2c , Pt 5c and Pt 6c modes could decelerate the O v migration effectively, especially in Pt 6c mode. Under oxygen-rich conditions, Pt 6c substitution could make oxygen O v formation easier, but migration harder. On Pt 6c /Ti 1− y O 2− x 1 (110) surface, as a bimetal center, Pt 4c -Ti 5c concave could not make water dissociation process easier; however, the O 2c closed to Pt become a good proton acceptor to make water dissociation on Ti 5c -O 2c more convenient with the aid of topmost Ti 5c .