Jo Seunghwan, Shin Ki Hoon, Kim Eunmin, Sohn Jung Inn
Department of Physics, Dongguk University, Seoul, 04620, Republic of Korea.
Small. 2025 Mar;21(10):e2411883. doi: 10.1002/smll.202411883. Epub 2025 Jan 29.
The hydrogen spillover phenomenon provides an expeditious reaction pathway via hydrogen transfer from a strong H adsorption site to a weak H adsorption site, enabling a cost-efficient hydrogen evolution reaction (HER) analogous to platinum with moderate H adsorption energy. Here, a high-entropy oxychalcogenide (HEOC) comprising Co, Ni, Mo, W, O, Se, and Te is prepared by a two-step electrochemical deposition for hydrogen spillover-enhanced HER in acidic and alkaline water electrolysis. The anodic-cathodic reversal current enables the co-deposition of cations and aliovalent anions, facilitating a glass structure with multiple active sites for hydrogen spillover. The HEOC exhibits low overpotentials of 52 and 57 mV to obtain a current density of 10 mA cm in acidic and alkaline media, respectively, and long-term stability for 500 h. The electrochemical and analytical approaches elucidate the hydrogen transfer toward Mo/W-O sites in both acid and alkaline HERs. Meanwhile, the other sites act as hydrogen adsorption or water dissociation-derived hydroxide adsorption sites, showing accommodable behavior in acidic and alkaline media. The HEOC exhibits a practically high current of 1 A cm at cell voltages of 1.78 and 1.89 V and long-term stability for 100 h in proton and anion exchange membrane water electrolyzers, respectively.
氢溢流现象提供了一条快速反应途径，即通过氢从强氢吸附位点转移到弱氢吸附位点，从而实现类似于具有适度氢吸附能的铂的低成本析氢反应（HER）。在此，通过两步电化学沉积制备了一种包含Co、Ni、Mo、W、O、Se和Te的高熵氧族硫属化物（HEOC），用于在酸性和碱性水电解中实现氢溢流增强的HER。阳极 - 阴极反向电流使得阳离子和异价阴离子能够共沉积，促进形成具有多个氢溢流活性位点的玻璃结构。HEOC在酸性和碱性介质中分别表现出低过电位，即达到10 mA cm²电流密度时分别为52和57 mV，并且具有500小时的长期稳定性。电化学和分析方法阐明了在酸性和碱性HER中氢向Mo/W - O位点的转移。同时，其他位点充当氢吸附或水离解衍生的氢氧化物吸附位点，在酸性和碱性介质中表现出适应性行为。在质子交换膜和阴离子交换膜水电解槽中，HEOC在电池电压为1.78和1.89 V时分别表现出高达1 A cm²的实际高电流以及100小时的长期稳定性。
