Fe-modified Co2(OH)3Cl microspheres for highly efficient oxygen evolution reaction

Wei Wang; Yunlei Zhong; Xinyu Zhang; Sainan Zhu; Yourong Tao; Yanxin Zhang; Hongsen Zhu; Yifei Zhang; Xingcai Wu; Guo Hong

doi:10.1016/j.jcis.2020.08.095

Fe-modified Co₂(OH)₃Cl microspheres for highly efficient oxygen evolution reaction

J Colloid Interface Sci. 2021 Jan 15;582(Pt B):803-814. doi: 10.1016/j.jcis.2020.08.095. Epub 2020 Aug 29.

Authors

Wei Wang¹, Yunlei Zhong², Xinyu Zhang¹, Sainan Zhu¹, Yourong Tao¹, Yanxin Zhang¹, Hongsen Zhu¹, Yifei Zhang¹, Xingcai Wu³, Guo Hong⁴

Affiliations

¹ Key Laboratory of Mesoscopic Chemistry of MOE, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
² Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa 999078, Macau; Department of Physics and Chemistry, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa 999078, Macau.
³ Key Laboratory of Mesoscopic Chemistry of MOE, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China. Electronic address: wuxingca@nju.edu.cn.
⁴ Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa 999078, Macau; Department of Physics and Chemistry, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa 999078, Macau. Electronic address: ghong@um.edu.mo.

PMID: 32916576
DOI: 10.1016/j.jcis.2020.08.095

Abstract

Surface self-reconstruction by the electrochemical activation is considered as an effective strategy to increase the oxygen evolution reaction (OER) performance of transition metal compounds. Herein, uniform Co₂(OH)₃Cl microspheres are developed and present an activation-enhanced OER performance caused by the etching of lattice Cl^- after 500 cyclic voltammetry (CV) cycles. Furthermore, the OER activity of Co₂(OH)₃Cl can be further enhanced after small amounts of Fe modification (Fe²⁺ as precursor). Fe doping into Co₂(OH)₃Cl lattices can make the etching of surface lattice Cl^- easier and generate more surface vacancies to absorb oxygen species. Meanwhile, small amounts of Fe modification can result in a moderate surface oxygen adsorption affinity, facilitating the activation of intermediate oxygen species. Consequently, the 10% Fe-Co₂(OH)₃Cl exhibits a superior OER activity with a lower overpotential of 273 mV at 10 mA cm^-2 (after 500 CV cycles) along with an excellent stability as compared with commercial RuO₂.

Keywords: Cobalt oxychloride; Fe modification; Oxygen evolution reaction; Surface self-reconstruction.