title: Catalytically Active Rh Sub-Nanoclusters on TiO2 for CO Oxidation at Cryogenic Temperatures.
abstract: The discovery that gold catalysts could be active for CO oxidation at cryogenic temperatures has ignited much excitement in nanocatalysis. Whether the alternative Pt group metal (PGM) catalysts can exhibit such high performance is an interesting research issue. So far, no PGM catalyst shows activity for CO oxidation at cryogenic temperatures. In this work, we report a sub-nano Rh/TiO2 catalyst that can completely convert CO at 223 K. This catalyst exhibits at least three orders of magnitude higher turnover frequency (TOF) than the best Rh-based catalysts and comparable to the well-known Au/TiO2 for CO oxidation. The specific size range of 0.4-0.8 nm Rh clusters is critical to the facile activation of O2 over the Rh-TiO2 interface in a form of Rh-O-O-Ti (superoxide). This superoxide is ready to react with the CO adsorbed on TiO2 sites at cryogenic temperatures.
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Hongling
authors.initials: H
authors.lastname: Guan
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Botao
authors.initials: B
authors.lastname: Qiao
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Miao
authors.affiliation: Department of Physics, Arizona State University, Tempe, AZ, 85287, USA.
authors.forename: Jingyue
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Aiqin
authors.initials: A
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China. xdwang@dicp.ac.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China. taozhang@dicp.ac.cn.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
keywords: carbon monoxide oxidation; catalysis; clusters; cryogenic temperatures; rhodium