Shen Wei, Zheng Yao, Hu Yang, Jin Jing, Hou Yichao, Zhang Nan, An Li, Xi Pinxian, Yan Chun-Hua
State Key Laboratory of Applied Organic Chemistry, Frontiers Science Center for Rare Isotopes, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, South Australia 5005, Australia.
J Am Chem Soc. 2024 Feb 28;146(8):5324-5332. doi: 10.1021/jacs.3c11861. Epub 2024 Feb 14.
The low coverage rate of anode OH adsorption under high current density conditions has become an important factor restricting the development of an industrial alkaline water electrolyzer (AWE). Here, we present our rare earth modification promotion strategy on using the rare earth oxygen-friendly interface to increase the OH coverage of the NiS surface for efficient AWE anode catalysis. Density functional theory calculations predict that rare earths can enhance the coverage of surface OH, and the synthesis reaction mechanism is discussed in the synthesis process spectrum. Experimentally, by preparing a series of rare-earth-modified NiS, the relationship between OH coverage, active site density, and catalytic activity was established by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, time-resolved absorption spectra, and so on. The unique oxygenophilic properties of rare earths enhance OH coverage, thereby increasing the density of active sites for efficient catalysis. Furthermore, EuO/NiS was assembled into the AWE equipment and operated stably for over 240 h at a current density of 300 mA cm under industrial conditions of 80 °C and 30% KOH. Rare-earth-modified NiS exhibits better catalytic activity than traditional non-noble metal anode catalysts Ni(OH) and NiS, providing a new approach for rare earth promotion to solve the problem of low OH coverage in the AWE anode.
在高电流密度条件下阳极OH吸附覆盖率较低已成为制约工业碱性水电解槽（AWE）发展的重要因素。在此，我们提出了一种稀土改性促进策略，即利用稀土亲氧界面提高NiS表面的OH覆盖率，以实现高效的AWE阳极催化。密度泛函理论计算预测，稀土可提高表面OH的覆盖率，并在合成过程谱中讨论了合成反应机理。实验上，通过制备一系列稀土改性的NiS，利用衰减全反射傅里叶变换红外光谱（ATR-FTIR）、时间分辨吸收光谱等手段，建立了OH覆盖率、活性位点密度与催化活性之间的关系。稀土独特的亲氧性质提高了OH覆盖率，从而增加了高效催化的活性位点密度。此外，将EuO/NiS组装到AWE设备中，并在80℃和30%KOH的工业条件下，于300mA cm的电流密度下稳定运行超过240小时。稀土改性的NiS表现出比传统非贵金属阳极催化剂Ni(OH)和NiS更好的催化活性，为稀土促进解决AWE阳极中OH覆盖率低的问题提供了一种新方法。
