Acta Phys. -Chim. Sin. ›› 2024, Vol. 40 ›› Issue (8): 2308003.doi: 10.3866/PKU.WHXB202308003

Special Issue: Electrocatalytic Functional Materials

• ARTICLE • Previous Articles     Next Articles

Bimetal Leaching Induced Reconstruction of Water Oxidation Electrocatalyst for Enhanced Activity and Stability

Wentao Xu1, Xuyan Mo1, Yang Zhou1, Zuxian Weng1, Kunling Mo1, Yanhua Wu1, Xinlin Jiang1, Dan Li1, Tangqi Lan1, Huan Wen2, Fuqin Zheng1,*(), Youjun Fan1,*(), Wei Chen1,*()   

  1. 1 School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, Guangxi, China
    2 Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
  • Received:2023-08-01 Revised:2023-09-22 Accepted:2023-09-22 Published:2023-10-09
  • Contact: Email: fqzheng@mailbox.gxnu.edu.cn (Fuqin Zheng)youjunfan@mailbox.gxnu.edu.cn (Youjun Fan)weichen@gxnu.edu.cn (Wei Chen)
  • Supported by:
    the Natural Science Foundation of Guangxi, China(2019GXNSFGA245003); the Natural Science Foundation of Guangxi, China(2021GXNSFBA220058); the National Natural Science Foundation of China(22002026); the National Natural Science Foundation of China(22272036); the Guangxi Technology Base and Talent Subject, China(GUIKE AD23026272); the Guangxi Normal University Research Grant, China(2022TD)

Abstract:

Surface reconstruction inevitably occurs during pre-catalysis for the oxygen evolution reaction (OER); however, obtaining OER electrocatalysts with high performance and stability remains a challenge. In this study, we have developed a bimetallic leaching-induced surface reconstruction strategy to fabricate efficient electrocatalysts for water oxidation. Microcolumn arrays consisting of α-CoMoO4, K2Co2(MoO4)3, Co3O4, and CoFe2O4 four-phase oxides were integrated as pre-catalyst by a hydrothermal, ion-exchange, and subsequent annealing process. In situ Raman spectroelectrochemical and ex situ X-ray diffraction (XRD) studies revealed that the rapid dissolution of the unstable component K2Co2(MoO4)3 triggered the adaptive leaching of Mo and K, which accelerated the transformation of the surface-enriched α-Co(OH)2 to the active phase of CoOOH at low voltage. Furthermore, the stable CoFe2O4 component couples the reconfigured new phase CoO with the amorphous layer CoOOH to form a compact hierarchical structure of CoFe2O4@CoO@CoOOH, which plays the role of a nanofence and effectively prevents the catalyst from over-reconstruction, thus achieving excellent catalytic stability. This work provides a novel idea for designing OER catalysts with excellent activity and stability at high current densities.

Key words: Oxygen evolution reaction, Surface reconstruction, Ion leaching, Water splitting, Electrocatalysis, Catalyst