Interplay between invasive single atom Pt and native oxygen vacancy in rutile TiO2(110) surface: A theoretical study
Xiaoyang Wang, Liang Zhang, Yuxiang Bu, Wenming Sun
Abstract
Oxygen vacancy (Ov) as well as Ov 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 Ov in SA-Pt/rutile TiO2(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, Pt2c, Pt5c and Pt6c modes could decelerate the Ov migration effectively, especially in Pt6c mode. Under oxygen-rich conditions, Pt6c substitution could make oxygen Ov formation easier, but migration harder. On Pt6c/Ti1−yO2−x1(110) surface, as a bimetal center, Pt4c-Ti5c concave could not make water dissociation process easier; however, the O2c closed to Pt become a good proton acceptor to make water dissociation on Ti5c-O2c more convenient with the aid of topmost Ti5c.