In-situ structure reconstitution of NiCo2Px for enhanced electrochemical water oxidation

作     者：Xue Bai Zhiyu Ren Shichao Du Huiyuan Meng Jun Wu Yuzhu Xue Xiaojun Zhao Honggang Fu 

作者机构：Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry Ministry of Education of the People's Republic of China Tianjin Normal University Tianjin 300387 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China 

出 版 物：《科学通报：英文版》 (Chinese Science Bulletin)

年 卷 期：2017年第62卷第22期

页      面：1510-1518页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：supported by the National Natural Science Foundation of China (21631004, 21371053,and 21573062) the Science Fund for Distinguished Young Scholar of Heilongjiang University (JCL201501) the Fundamental Research Funds for the Heilongjiang University of Heilongjiang Province of China(HDRCCX2016202) 

主　　题：NiCo2Px Structure reconstitution Anodic oxidation CoNi(OOH)x Oxygen evolution reaction(OER) 

摘      要：Gaining insight into the structure evolution of transition-metal phosphides during anodic oxidation is significant to understand their oxygen evolution reaction(OER) mechanism, and then design highefficiency transition metal-based catalysts. Herein, NiCo_2P_x nanowires(NWs) vertically grown on Ni foam were adopted as the target to explore the in-situ morphology and chemical component reconstitution during the anodic oxidation. The major factors causing the transformation from NiCo_2P_x into the hierarchical NiCo_2P_x@CoNi(OOH)_x NWs are two competing reactions: the dissolution of NiCo_2P_x NWs and the oxidative re-deposition of dissolved Co^(2+) and Ni^(2+) ions, which is based primarily on the anodic bias applied on NiCo2 Px NWs. The well balance of above competing reactions, and local pH on the surface of NiCo_2P_x NW modulated by the anodic oxidation can serve to control the anodic electrodeposition and rearrangement of metal ions on the surface of NiCo_2P_x NWs, and the immediate conversion into CoNi(OOH)_x. Consequently, the regular hexagonal CoNi(OOH)_x nanosheets grew around NiCo_2P_x *** from the active catalytic sites on the surface and the sufficient conductivity, the resultant NiCo_2P_x@CoNi(OOH)_x arrays also display good OER activity, in terms of the fast kinetics process, the high energy conversion efficiency, especially the excellent durability. The strategy of in-situ structure reconstitution by electrochemical reaction described here offers a reliable and valid way to construct the highly active systems for various electrocatalytic applications.