Song Haoyu, Xiong Xiaolu, Gao Jinxiao, Hu Yue, Yang Qun, Zheng Dehua, Hao Jingxuan, Lin Xiao, Zhang Linjuan, Wang Jian-Qiang
Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, P. R. China.
Shanghai Institute of Applied Physics Chinese Academy of Sciences, Shanghai, 201800, P. R. China.
Small. 2024 Nov;20(48):e2404060. doi: 10.1002/smll.202404060. Epub 2024 Sep 5.
In recent years, catalysts based on transition metal sulfides have garnered extensive attention due to their low cost and excellent electrocatalytic activity in the alkaline oxygen evolution reaction. Here, the preparation of Fe-doped NiS via a one-step hydrothermal approach is reported by utilizing inexpensive transition metals Ni and Fe. In an alkaline medium, Fe-NiS exhibits outstanding electrocatalytic activity and stability for the OER, and the current density can reach 10 mA cm with an overpotential of 163 mV. In addition, Pt/C||Fe-NiS is used as the membrane electrode of the anion exchange membrane water electrolyzer, which is capable of providing a current density of 650 mA cm at a cell voltage of 2.0 V, outperforming the benchmark Ir/C. The principle is revealed that the doping of Fe enhances the electrocatalytic water decomposition ability of NiS by in situ Raman and in situ X-ray absorption fine structure. The results indicate that the doping of Fe decreases the charge density near Ni atoms, which renders Fe-NiS more favorable for the adsorption of OH and the formation of OO intermediates. This work puts forward an effective strategy to significantly improve both the alkaline OER activity and stability of low-cost electrocatalysts.
近年来，基于过渡金属硫化物的催化剂因其低成本以及在碱性析氧反应中出色的电催化活性而受到广泛关注。在此，报道了通过利用廉价的过渡金属镍和铁，采用一步水热法制备铁掺杂硫化镍。在碱性介质中，铁掺杂硫化镍对析氧反应表现出出色的电催化活性和稳定性，电流密度可达10 mA cm²，过电位为163 mV。此外，铂碳||铁掺杂硫化镍用作阴离子交换膜水电解槽的膜电极，在2.0 V的电池电压下能够提供650 mA cm²的电流密度，性能优于基准铱碳。通过原位拉曼光谱和原位X射线吸收精细结构揭示了铁掺杂通过增强硫化镍的电催化水分解能力的原理。结果表明，铁掺杂降低了镍原子附近的电荷密度，这使得铁掺杂硫化镍更有利于羟基的吸附和氧氧中间体的形成。这项工作提出了一种有效策略，可显著提高低成本电催化剂的碱性析氧活性和稳定性。
