Zhao Sheng, Wang Yue, Hao Yixin, Yin Lijie, Kuo Chun-Han, Chen Han-Yi, Li Linlin, Peng Shengjie
College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China.
Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan.
Adv Mater. 2024 Feb;36(7):e2308925. doi: 10.1002/adma.202308925. Epub 2023 Dec 7.
Neutral oxygen evolution reaction (OER) with unique reactive environments exhibits extremely slow reaction kinetics, posing significant challenges in the design of catalysts. Herein, a built-in electric field between the tungstate (Ni-FeWO ) with adjustable work function and Lewis acid WO is elaborately constructed to regulate asymmetric interfacial electron distribution, which promotes electron accumulation of Fe sites in the tungstate. This decelerates the rapid dissolution of Fe under the OER potentials, thereby retaining the active hydroxyl oxide with the optimized OER reaction pathway. Meanwhile, Lewis acid WO enhances hydroxyl adsorption near the electrode surface to improve mass transfer. As expected, the optimized Ni-FeWO @WO /NF self-supporting electrode achieves a low overpotential of 235 mV at 10 mA cm in neutral media and maintains stable operation for 200 h. Furthermore, the membrane electrode assembly constructed by such self-supporting electrode exhibits robust stability for 250 h during neutral seawater electrolysis. This work deepens the understanding of the reconstruction of OER catalysts in neutral environments and paves the way for development of the energy conversion technologies.
具有独特反应环境的中性析氧反应(OER)表现出极其缓慢的反应动力学,这给催化剂的设计带来了重大挑战。在此,精心构建了具有可调功函数的钨酸盐(Ni-FeWO )与路易斯酸WO 之间的内建电场,以调节不对称界面电子分布,促进钨酸盐中Fe位点的电子积累。这减缓了Fe在OER电位下的快速溶解,从而保留了具有优化OER反应途径的活性羟基氧化物。同时,路易斯酸WO增强了电极表面附近的羟基吸附,以改善传质。正如预期的那样,优化后的Ni-FeWO @WO /NF自支撑电极在中性介质中10 mA cm 下实现了235 mV的低过电位,并保持200 h的稳定运行。此外,由这种自支撑电极构建的膜电极组件在中性海水电解过程中表现出250 h的强大稳定性。这项工作加深了对中性环境中OER催化剂重构的理解,并为能量转换技术的发展铺平了道路。