title: Self-supported three-dimensional mesoporous semimetallic WP2nanowire arrays on carbon cloth as a flexible cathode for efficient hydrogen evolution.
abstract: The design and development of high-efficiency and non-noble metal hydrogen evolution reaction (HER) electrocatalysts with optimized nanostructures for human clean and sustainable energy systems has attracted significant research interest over the past years. Herein, self-supported semimetallic tungsten diphosphide nanowire arrays on carbon cloth (WP2NWs/CC) were topotactically fabricated by in situ phosphidation of a WO3NWs/CC precursor. Such a binder-free flexible HER cathode with integrated three-dimensional nanostructures can not only provide a large surface area to expose abundant active sites, but also facilitate electrolyte penetration for electrons and electrolyte ions. The WP2NWs/CC electrode exhibits superior catalytic performance, and it needs overpotentials of 109 and 160 mV with a small Tafel slope of 56 mV dec-1to achieve current densities of 10 and 50 mA cm-2, respectively. High stability in acidic media is also observed for the catalyst for a duration of 20 hours at least. In addition, density functional theory (DFT) calculations indicate a low kinetic energy barrier for H atom adsorption on the WP2surface which guarantees the excellent catalytic activity of the catalyst, and the influences of phosphidation temperature on the HER activity are also studied. The excellent electrocatalytic activity makes the present 3D structured WP2NWs/CC a promising catalyst for large scale highly pure hydrogen evolution by electrochemical water splitting.
authors.affiliation: School of Physics, Chongqing University, Chongqing, 401331, China. sjchen@cqu.edu.cn wangshuxia@cqu.edu.cn.
authors.forename: Mingyu
authors.initials: M
authors.lastname: Pi
authors.affiliation: School of Physics, Chongqing University, Chongqing, 401331, China. sjchen@cqu.edu.cn wangshuxia@cqu.edu.cn.
authors.forename: Tianli
authors.initials: T
authors.lastname: Wu
authors.affiliation: College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing, 401331, China.
authors.forename: Dingke
authors.initials: D
authors.lastname: Zhang
authors.affiliation: School of Physics, Chongqing University, Chongqing, 401331, China. sjchen@cqu.edu.cn wangshuxia@cqu.edu.cn.
authors.forename: Shijian
authors.initials: S
authors.lastname: Chen
authors.affiliation: School of Physics, Chongqing University, Chongqing, 401331, China. sjchen@cqu.edu.cn wangshuxia@cqu.edu.cn.
authors.forename: Shuxia
authors.initials: S
authors.lastname: Wang