Effects of a TiC substrate on the catalytic activity of Pt for NO reduction.
Density functional theory calculations are used to elucidate the catalytic properties of a Pt monolayer supported on a TiC(001) substrate (Pt/TiC) toward NO reduction. It is found that the compound system of Pt/TiC has a good stability due to the strong Pt-TiC interaction. The diverse dissociation paths (namely the direct dissociation mechanism and the dimeric mechanism) are investigated. The transition state searching calculations suggest that NO has strong diffusion ability and small activation energy for dissociation on the Pt/TiC. For NO reduction on the Pt/TiC surface, we have found that the direct dissociation mechanisms (NO + N + O → NO2 + N and NO + N + O → N2 + O + O) are easier with a smaller dissociation barrier than those on the Pt(111) surface; and the dimeric process (NO + NO → (NO)2 → N2O + O → N2 + O + O) is considered to be dominant or significant with even a lower energy barrier than that of the direct dissociation. The results show that Pt/TiC can serve as an efficient catalyst for NO reduction.
College of Physics and Electronic Engineering, Henan Normal University, Xinxiang, Henan 453007, China. yzx@henannu.edu.cn.
Xingli
X
Chu
College of Physics and Electronic Engineering, Henan Normal University, Xinxiang, Henan 453007, China. yzx@henannu.edu.cn.
Zhaoming
Z
Fu
Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
Shasha
S
Li
College of Physics and Electronic Engineering, Henan Normal University, Xinxiang, Henan 453007, China. yzx@henannu.edu.cn.
Xilin
X
Zhang
College of Physics and Electronic Engineering, Henan Normal University, Xinxiang, Henan 453007, China. yzx@henannu.edu.cn and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan Province, China.
Zongxian
Z
Yang