title: CoOOH Nanosheets with High Mass Activity for Water Oxidation.
abstract: Endowing transition-metal oxide electrocatalysts with high water oxidation activity is greatly desired for production of clean and sustainable chemical fuels. Here, we present an atomically thin cobalt oxyhydroxide (γ-CoOOH) nanosheet as an efficient electrocatalyst for water oxidation. The 1.4 nm thick γ-CoOOH nanosheet electrocatalyst can effectively oxidize water with extraordinarily large mass activities of 66.6 A g(-1), 20 times higher than that of γ-CoOOH bulk and 2.4 times higher than that of the benchmarking IrO2 electrocatalyst. Experimental characterizations and first-principles calculations provide solid evidence to the half-metallic nature of the as-prepared nanosheets with local structure distortion of the surface CoO(6-x) octahedron. This greatly enhances the electrophilicity of H2O and facilitates the interfacial electron transfer between Co ions and adsorbed -OOH species to form O2, resulting in the high electrocatalytic activity of layered CoOOH for water oxidation.
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Junheng
authors.initials: J
authors.lastname: Huang
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Junting
authors.initials: J
authors.lastname: Chen
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Tao
authors.initials: T
authors.lastname: Yao
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Jingfu
authors.initials: J
authors.lastname: He
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Shan
authors.initials: S
authors.lastname: Jiang
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Zhihu
authors.initials: Z
authors.lastname: Sun
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China). qhliu@ustc.edu.cn.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Liu
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Weiren
authors.initials: W
authors.lastname: Cheng
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Fengchun
authors.initials: F
authors.lastname: Hu
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China).
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China). zhypan@ustc.edu.cn.
authors.forename: Zhiyun
authors.initials: Z
authors.lastname: Pan
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (P.R. China). sqwei@ustc.edu.cn.
authors.forename: Shiqiang
authors.initials: S
authors.lastname: Wei
keywords: XAFS; electrocatalysis; half-metallic; water oxidation; γ-CoOOH nanosheets