半极性ZnO(101)表面负载Au催化CO氢助氧化的计算研究

Computational study of H-assisted CO oxidation by gold catalyst supported on semi-polar ZnO(101) surface

本文利用半极性ZnO（101）表面负载Au团簇模型，通过密度泛函理论计算，对比研究Au／ZnO界面催化CO氢助氧化机理，探究H和Au的协同催化作用．结果表明：Au／ZnO（101）催化CO氧化活性较低，能垒为1．45eV；在氢助条件下，活性大大提高，能垒仅为0．48eV，这主要归因于H有助于促进O2解离．该研究为理解Au／ZnO界面H／OH的协同催化作用提供了新的认识．

In this article, we carried out density functional theory calculations of CO oxidation by gold clusters supported on semi-polar ZnO（101） surface. Both pristine and H-assisted CO oxidations were compared to explore the co-catalysis of H/OH species for Au/ZnO catalyst. Results indicate that both dissociative and associative Langmuir-Hinshelwood （L-H） mechanisms are facilitated by the assistance of H on ZnO（101） surface for CO oxidation. The reaction energy barriers （0.48 and 0.96 eV） of H- assisted CO oxidation are much lower than those （2.16 and 1.45 eV） without H, especially for the dissociative L-H pathway because H facilitates the dissociation of dioxygen. This study provides new insights into the synergistic effect between interfacial H/OH species and supported gold catalyst.