Wang Zhichao, Feng Junjie, Chen Si, Yang Guosheng, Wang Jie, Qiu Tiandong, Li Chuncheng, He Xiangyu, Zhang Yufeng, Huang Wenli, Li Ming, Zhu Yachao, Hu Dan, Deng Jie
College of Food and Biological Engineering, College of Chemistry and Chemical Engineering, Chengdu University, Chengdu 610106, China.
Sichuan Institute of Product Quality Supervision and Inspection, Chengdu 610000, China.
J Colloid Interface Sci. 2025 Dec;699(Pt 2):138243. doi: 10.1016/j.jcis.2025.138243. Epub 2025 Jun 23.
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, rapid kinetics (54.1 mV/dec) and prominent durability of >693 h to maintain the initial current density of 100 mA cm. 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.
高价镍（铁）金属被认为是实用的电活性相，在碱性析氧反应（OER）过程中能够加速反应动力学并展现出高固有反应活性。然而，它们的形成和稳定在热力学上是不利的。氧阴离子具有独特的聚阴离子结构单元和合适的电负性，使其能够与相邻金属阳离子共享更多分散的电子，从而平衡金属阳离子的强正电场。与传统的金属阳离子或非金属阴离子修饰相比，这一特性为调节表面自重构提供了一种更有利的方法。基于此，本文提出了一种氧硫化物阴离子调控方法以获得稳定的高价镍（铁）相。通过简单地将商用泡沫镍铁在过硫酸铵和水的低温反应介质中处理，氧硫化物阴离子可以直接预锚定到氢氧化镍（铁）海胆阵列催化剂上。预键合的氧硫化物能够有效地调整电活性位点的电子能级（例如氧化态工程、带隙变窄、金属 - 氧共价性和金属d带中心），从而改变表面电荷转移速率，进一步增强OER中间体的吸附、转化和解吸。最终，加速了OER动力学，并能够克服持续的*OH - *OOH标度关系以降低过电位。最终的催化剂在10 mA cm时具有219 mV的低过电位、快速的动力学（54.1 mV/dec）以及大于693 h的突出耐久性，以维持100 mA cm的初始电流密度，展现出优异的OER性能。对简单的低温热化学氧硫化物调制方案以及硫酸盐在提高OER活性中的作用的深入了解，能够拓宽对电催化中氧阴离子效应的认识，并为设计用于实际应用的前沿电催化剂提供合理的方法。
