J. Mater. Sci. Technol. ›› 2025, Vol. 239: 320-329.DOI: 10.1016/j.jmst.2025.03.056

• Research Article • Previous Articles     Next Articles

Cr-leaching induced in-situ surface reconstruction of trimetallic CoFeCr-hydroxide on Ni foam for highly efficient water oxidation

Xiaorui Wanga,1, Lingxing Zana,1,*, Hongling Zhanga, Kun Tiana, Dan Zhua, Jian Lib, Qiang Wengc, Cuicui Wangd, Qingbo Weia, Wenlin Zhanga,*, Xiangyang Houa,*, Feng Fua,*   

  1. aKey Laboratory of Chemical Reaction Engineering of Shaanxi Province; College of Chemistry & Chemical Engineering, Yan'an University, Yan'an 716000, China;
    bSchool of Chemistry and Chemical Engineering, Yulin University, Yulin 718000, China;
    cSchool of Materials Science and Engineering, Shaanxi Normal University, Xi'an 710119, China;
    dMaterial R&D Center, Goertek Inc., Weifang 261031, China
  • Received:2024-12-31 Revised:2025-03-19 Accepted:2025-03-29 Published:2025-12-20 Online:2025-04-30
  • Contact: *E-mail addresses: zanlingxing@yau.edu.cn (L. Zan), thuwlzhang@163.com (W. Zhang), hxy2248@163.com (X. Hou), yadxfufeng@126.com (F. Fu)
  • About author:1These authors contributed equally to this work.

Abstract: Rationally regulating the inevitable dynamic evolution of the catalyst surface structure towards high efficiency for water electrolysis remains a significant challenge. Here, the ternary cobalt-iron-chromium double hydroxide (DH) was synthesized on nickel foam as a monolithic catalytic electrode (CoFeCr-DH/NF) for the oxygen evolution reaction (OER) via a simple electrodeposition technique. The optimized Co0.7Fe0.3Cr-DH/NF electrode exhibited remarkable catalytic activity and stability. The overpotential at the current density of 100 mA cm-2 is only 281 mV, far exceeding those of other monolithic catalytic electrodes. Furthermore, we elucidated the variations in the valence states of metals during the OER process and found the electrochemical oxidation of Co2+ to Co3+ and leaching of Cr. Importantly, Cr-leaching can induce surface reconstruction, which not only optimizes the surface electronic structure to enhance the intrinsic activity but also increases the surface irregularity to enlarge the electrochemically active surface area, thereby significantly improving the OER performance. Theoretical calculations revealed that OER preferentially occurred at the adjacent Cr-leached Co sites and confirmed that the Cr-leached trimetallic CoFeCr-DH performs an outstanding OER performance.

Key words: Cobalt-iron-chromium double hydroxides (CoFeCr-DH), Cr-leaching, Surface reconstruction, Oxygen evolution reaction (OER), Catalytic activity