title: Oxygen vacancies as active sites for H2S dissociation on the rutile TiO2(110) surface: a first-principles study.
abstract: Spin-polarized DFT+U computations have been performed to investigate the role of oxygen vacancies in dissociating H2S on the rutile TiO2(110) surface. A bridged O2c atom is demonstrated to be the most energetically favorable oxygen vacancy site, which makes V(O2c) an electron donator center and induces an isolated defect level with narrowed band gaps. A H2S molecule is adsorbed dissociatively over V(O2c), but molecularly on the perfect surface. For H2S dissociation, the HS/H intermediate state reveals the best thermal stability on both defected and perfect surfaces. Moreover, potential energy surface analysis shows that V(O2c) reduces markedly the energy barriers for the paths along H2S dissociation. This indicates oxygen vacancies to be efficient trap centers for H2S dissociation, as evidenced by a significant interfacial charge transfer promoted by vacancies. This work could provide insights into the role of oxygen vacancies in facilitating the decomposition of H2S on rutile TiO2(110) surface.
authors.affiliation: State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China. yzhou@swpu.edu.cn yzhou44@126.com and The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China.
authors.forename: Shiqian
authors.initials: S
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China. yzhou@swpu.edu.cn yzhou44@126.com.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, University of Zurich, 8057 Zurich, Switzerland.
authors.forename: Great R
authors.initials: GR
authors.lastname: Patzke
authors.affiliation: State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China. yzhou@swpu.edu.cn yzhou44@126.com and The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou