Wang Sangni, Yuan Ding, Sun Sihan, Huang Shuhan, Wu Yuheng, Zhang Lei, Dou Shi Xue, Liu Hua Kun, Dou Yuhai, Xu Jiantie
National Engineering Laboratory for VOCs Pollution Control Technology and Equipment, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control School of Environment and Energy, South China University of Technology, Guangzhou, 510640, China.
Institute of Energy Materials Science, University of Shanghai for Science and Technology, Shanghai, 200093, China.
Small. 2024 Sep;20(36):e2311770. doi: 10.1002/smll.202311770. Epub 2024 May 25.
Developing low-cost and highly efficient bifunctional catalysts for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is a challenging problem in electrochemical overall water splitting. Here, iron, tungsten dual-doped nickel sulfide catalyst (Fe/W-NiS) is synthesized on the nickel foam, and it exhibits excellent OER and HER performance. As a result, the water electrolyze based on Fe/W-NiS bifunctional catalyst illustrates 10 mA cm at 1.69 V (without iR-compensation) and highly durable overall water splitting over 100 h tested under 500 mA cm. Experimental results and DFT calculations indicate that the synergistic interaction between Fe doping and Ni vacancy induced by W leaching during the in situ oxidation process can maximize exposed OER active sites on the reconstructed NiOOH species for accelerating OER kinetics, while the Fe/W dual-doping optimizes the electronic structure of Fe/W-NiS and the binding strength of intermediates for boosting HER. This study unlocks the different promoting mechanisms of incorporating Fe and W for boosting the OER and HER activity of NiS for water splitting, which provides significant guidance for designing high-performance bifunctional catalysts for overall water splitting.
开发用于析氧反应（OER）和析氢反应（HER）的低成本、高效双功能催化剂是电化学全水解中的一个具有挑战性的问题。在此，在泡沫镍上合成了铁、钨双掺杂硫化镍催化剂（Fe/W-NiS），其表现出优异的OER和HER性能。因此，基于Fe/W-NiS双功能催化剂的水电解槽在1.69 V（无iR补偿）下实现了10 mA cm的电流密度，并且在500 mA cm的电流密度下经过100 h测试表现出高度持久的全水解性能。实验结果和密度泛函理论（DFT）计算表明，原位氧化过程中由钨浸出诱导的铁掺杂与镍空位之间的协同相互作用可使重构的NiOOH物种上暴露的OER活性位点最大化，从而加速OER动力学，而铁/钨双掺杂优化了Fe/W-NiS的电子结构以及中间体的结合强度，以促进HER。本研究揭示了掺入铁和钨对提高NiS用于水分解的OER和HER活性的不同促进机制，为设计用于全水解的高性能双功能催化剂提供了重要指导。
