Tuning oxygen vacancies in two-dimensional iron-cobalt oxide nanosheets through hydrogenation for enhanced oxygen evolution activity

作     者：Linzhou Zhuang Yi Jia Tianwei He Aijun Du Xuecheng Yan Lei Ge Zhonghua Zhu Xiangdong Yao 

作者机构：School of Chemical Engineering The University of Queensland Brisbane 4072 Australia School of Environment and Science and Queensland Micro- and Nanotechnology Centre Griffith University Nathan Campus Brisbane 4111 Australia School of Chemistry Physics and Mechanical Engineering Queensland University of Technology Gardens Point Campus Brisbane 4001 Australia 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2018年第11卷第6期

页      面：3509-3518页

核心收录：

学科分类：081702[工学-化学工艺] 080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：support from ARC is highly appreciated, through ARC Discovery Project ARC Future Fellowship ARC Discovery Early Career Researcher Award the support from International Postgraduate Research Scholarship (IPRS) and UQ Centennial Scholarship (UQCent) 

主　　题：hydrogenation tuning oxygen vacancy oxygen evolution reaction 

摘      要：The oxygen evolution reaction （OER） represents the rate-determining step of electrocatalytic water splitting into hydrogen and oxygen. Creating oxygen vacancies and adjusting their density has proven to be an effective strategy to design high-performance OER catalysts. Herein, a hydrogenation method is applied to treat a two-dimensional （2D） iron-cobalt oxide （Fe1Co1Ox-origin）, with the purpose of tuning its oxygen vacancy density. Notably, compared with Fe1Co1Ox-origin, the iron-cobalt oxide hydrogenated at 200℃ and 2.0 MPa optimized conditions exhibits a markedly improved OER activity in 1.0 M KOH （with an overpotential 17 of 225 mV at a current density of 10 ***^-2） and a rapid reaction kinetics （with a Tafel slope of 36.0 mV·dec^-1）. Moreover, the OER mass activity of the hydrogenated oxide is 1.9 times that of Fe1Co1Ox-origin at an overpotential of 350 mV. The experimental results, combined with density functional theory （DFT） calculations, reveal that the optimal control of oxygen vacancies in 2D Fe1Co1Ox via hydrogenation can improve the electronic conductivity and promote OH- adsorption onto nearby low-coordinated Co^3＋ sites, resulting in a significantly enhanced OER activity.