文献类型：期刊文献

英文题名：Electrocatalyst with Dynamic Formation of the Dual-Active Site from the Dual Pathway Observed by In Situ Raman Spectroscopy

作者：Jing, Chao[1];Yuan, Taotao[1,2];Li, Lili[1];Li, Jianfeng[3];Qian, Zhengxin[3];Zhou, Jing[1];Wang, Yifeng[1];Xi, Shibo[4];Zhang, Nian[5];Lin, Hong-Ji[6];Chen, Chien-Te[6];Hu, Zhiwei[7];Li, Da-Wei[2];Zhang, Linjuan[1];Wang, Jian-Qiang[1]

机构：[1]Chinese Acad Sci, Shanghai Inst Appl Phys, Key Lab Interfacial Phys & Technol, Dept Hydrogen Tech, Shanghai 201800, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]Xiamen Univ, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China;[4]ASTAR, Inst Chem & Engn Sci, Singapore 138632, Singapore;[5]Chinese Acad Sci, Shanghai Inst Microsyst & Informat Technol, Shanghai 200050, Peoples R China;[6]Natl Synchrotron Radiat Res Ctr, Hsinchu 30076, Taiwan;[7]Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany

年份：2022

卷号：12

期号：16

起止页码：10276

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20223412622577);WOS:【SCI-EXPANDED(收录号:WOS:000874889800001)】；

语种：英文

外文关键词：in situ Raman spectroscopy; oxygen evolution reaction; cobalt hydroxide; structural transformation; reaction-rate dependent pathways

摘要：Understanding the catalysis mechanism of the sluggish oxygen evolution reaction (OER) involved in water splitting is of vital importance for the development of clean hydrogen energy. Earth-abundant transition-metal (oxy)hydroxide with low cost and high performance is one of the most promising OER catalysts. These catalysts often dynamically and heterogeneously transform from inactive pre-catalysts into active phases under operation conditions, and thus, the operando/in situ method is needed for the direct observation. Herein, using in situ Raman spectroscopy and density functional theory simulation, we correlate the OER activity with the dynamic crystal-and electronic-structure reconstruction of nano-sheet cobalt hydroxide. A complicated dual-transformation path is observed as the applied voltage is gradually increased; the pristine single-phase alpha-Co(OH)(2) catalyst transforms into the hydrous Co(OH)(2) phase through hydroxide intercalation, then to mixed beta/gamma-CoOOH phases through dehydration and dehydrogenation, and finally to OER-active gamma-CoOOHx and beta-CoOOHy. Moreover, the observed spectral and Tafel behaviors at different scan rates manifest the rate-dependent formation of the dual-active-phase, demonstrating the correlation between the OER ability and thermodynamics of structural reconstruction, which is critical in the fabrication of high-activity catalysts.