title: Single Silver Adatoms on Nanostructured Manganese Oxide Surfaces: Boosting Oxygen Activation for Benzene Abatement.
abstract: The involvement of a great amount of active oxygen species is a crucial requirement for catalytic oxidation of benzene, because complete mineralization of one benzene molecule needs 15 oxygen atoms. Here, we disperse single silver adatoms on nanostructured hollandite manganese oxide (HMO) surfaces by using a thermal diffusion method. The single-atom silver catalyst (Ag1/HMO) shows high catalytic activity in benzene oxidation, and 100% conversion is achieved at 220 °C at a high space velocity of 23 000 h-1. The Mars-van Krevelen mechanism is valid in our case as the reaction orders for both benzene and O2approach one, according to reaction kinetics data. Data from H2temperature-programmed reduction and O core-level X-ray photoelectron spectra (XPS) reveal that Ag1/HMO possesses a great amount of active surface lattice oxygen available for benzene oxidation. Valence-band XPS and density functional theoretical calculations demonstrate that the single Ag adatoms have the upshifted 4d orbitals, thus facilitating the activation of gaseous oxygen. Therefore, the excellent activation abilities of Ag1/HMO toward both surface lattice oxygen and gaseous oxygen account for its high catalytic activity in benzene oxidation. This work may assist with the rational design of efficient metal-oxide catalysts for the abatement of volatile organic compounds such as benzene.
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Yaxin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Meijuan
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Ma
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Chen
authors.affiliation: Institute of Atmospheric Sciences, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, China.|Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology , Nanjing, Jiangsu 210044, China.
authors.forename: Xingfu
authors.identifier: 0000-0002-0746-1294
authors.initials: X
authors.lastname: Tang
mesh_terms: D001554:Benzene; D002384:Catalysis; D010084:Oxidation-Reduction; D010100:Oxygen; D012834:Silver
chemical_list: D012834:Silver; D001554:Benzene; D010100:Oxygen