Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong, Wollongong, NSW, 2522, Australia.
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610068, P. R. China.
Chemistry. 2019 Jan 2;25(1):280-284. doi: 10.1002/chem.201803844. Epub 2018 Dec 11.
Electrochemical water splitting is one of the potential approaches for making renewable energy production and storage viable. The oxygen evolution reaction (OER), as a sluggish four-electron electrochemical reaction, has to overcome high overpotential to accomplish overall water splitting. Therefore, developing low-cost and highly active OER catalysts is the key for achieving efficient and economical water electrolysis. In this work, Fe-doped NiMoO was synthesized and evaluated as the OER catalyst in alkaline medium. Fe doping helps to regulate the electronic structure of Ni centers in NiMoO , which consequently promotes the catalytic activity of NiMoO . The overpotential to reach a current density of 10 mA cm is 299 mV in 1 m KOH for the optimal Ni Fe MoO , which is 65 mV lower than that for NiMoO . Further, the catalyst also shows exceptional performance stability during a 2 h chronopotentiometry testing. Moreover, the real catalytically active center of Ni Fe MoO is also unraveled based on the ex situ characterizations. These results provide new alternatives for precious-metal-free catalysts for alkaline OER and also expand the Fe-doping-induced synergistic effect towards performance enhancement to new catalyst systems.
电化学水分解是可再生能源生产和储存的一种有潜力的方法。析氧反应（OER）作为一个缓慢的四电子电化学过程，需要克服高过电势才能实现整体水分解。因此，开发低成本、高活性的 OER 催化剂是实现高效、经济水电解的关键。在这项工作中，合成了掺铁的 NiMoO 并将其评估为碱性介质中的 OER 催化剂。Fe 掺杂有助于调节 NiMoO 中 Ni 中心的电子结构，从而促进 NiMoO 的催化活性。对于最佳的 NiFeMoO，达到 10 mA cm 的电流密度的过电势为 299 mV，比 NiMoO 低 65 mV。此外，该催化剂在 2 小时恒电流计时测试中也表现出出色的稳定性。此外，还基于非原位表征揭示了 NiFeMoO 的实际催化活性中心。这些结果为碱性 OER 的无贵金属催化剂提供了新的选择，并将 Fe 掺杂诱导的协同效应扩展到新的催化剂体系，以提高性能。
