High-valent nickel oxyhydroxides self-derived through a low-temperature thermochemical strategy for an efficient oxygen evolution reaction

Zhichao Wang; Junjie Feng; Si Chen; Guosheng Yang; Jie Wang; Tiandong Qiu; Chuncheng Li; Xiangyu He; Yufeng Zhang; Wenli Huang; Ming Li; Yachao Zhu; Dan Hu; Jie Deng

doi:10.1016/j.jcis.2025.138243

High-valent nickel oxyhydroxides self-derived through a low-temperature thermochemical strategy for an efficient oxygen evolution reaction

J Colloid Interface Sci. 2025 Jun 23;699(Pt 2):138243. doi: 10.1016/j.jcis.2025.138243. Online ahead of print.

Authors

Zhichao Wang¹, Junjie Feng¹, Si Chen², Guosheng Yang³, Jie Wang¹, Tiandong Qiu⁴, Chuncheng Li⁴, Xiangyu He⁴, Yufeng Zhang⁵, Wenli Huang⁶, Ming Li², Yachao Zhu⁷, Dan Hu⁸, Jie Deng⁹

Affiliations

¹ College of Food and Biological Engineering, College of Chemistry and Chemical Engineering, Chengdu University, Chengdu 610106, China.
² Sichuan Institute of Product Quality Supervision and Inspection, Chengdu 610000, China.
³ School of Information Science and Engineering, Shandong University, 72 Binhai Road, Qingdao 266237, China.
⁴ School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, China.
⁵ School of Architecture and Civil Engineering, Chengdu University, Chengdu, China.
⁶ Biotechnology and Nuclear Technology Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China.
⁷ Institute of Future Technology, Southwest Jiaotong University, Chengdu 610031, China. Electronic address: yachao.zhu@swjtu.edu.cn.
⁸ Sichuan Institute of Product Quality Supervision and Inspection, Chengdu 610000, China. Electronic address: demyd03@163.com.
⁹ College of Food and Biological Engineering, College of Chemistry and Chemical Engineering, Chengdu University, Chengdu 610106, China; Institute for Advanced Study, Chengdu University, Chengdu 610106, China. Electronic address: dengjie@cdu.edu.cn.

PMID: 40580564
DOI: 10.1016/j.jcis.2025.138243

Abstract

High-valent Ni(Fe) metals are considered practical electroactive phases that can accelerate reaction kinetics and exhibit high inherent reactivity during the alkaline oxygen evolution reaction (OER). However, their formation and stabilisation are thermodynamically unfavourable. Oxyanions possess a unique polyanionic motif and suitable electronegativity, enabling them to share more dispersed electrons with adjacent metal cations and thereby balance the strong positive electronic fields of the metal cations. This characteristic offers a more favourable approach to modulate surface self-reconfiguration compared with conventional metal cation or non-metal anion modifications. Based on this, herein, an oxysulfide anion regulation method is proposed to obtain stable high-valent Ni(Fe) phases. The oxysulfide anion can be directly pre-anchored onto a Ni(Fe) oxyhydroxide sea-urchin array catalyst by simply treating the commercial NiFe foam in a low-temperature reaction medium of ammonium persulfate and water. The pre-bonded oxysulfide can effectively tailor the electronic energy level of electroactive sites (e.g. oxidation-state engineering, band gap narrowing, metal-O covalency and metal d-band centre), thereby altering the surface charge transfer rate to further enhance the adsorption, conversion and desorption of OER intermediates. Ultimately, the OER kinetics is accelerated, and the persistent *OH-*OOH scaling relationship can be overcome to reduce the overpotentials. The final catalyst achieves superior OER performance with a low overpotential of 219 mV at 10 mA cm^-2, rapid kinetics (54.1 mV/dec) and prominent durability of >693 h to maintain the initial current density of 100 mA cm^-2. Informative insights into both simple low-temperature thermochemical oxysulfide modulation protocol and sulfate-tuned roles in improving OER activity could broaden the understanding of the oxyanion effect in electrocatalysis and provide a rational approach for designing cutting-edge electrocatalysts for practical applications.

Keywords: Electronic structure; NiFe electrocatalyst; Oxygen evolution; Water splitting.