Key Laboratory of Special Functional Materials for Ecological Environment and Information, Hebei University of Technology, Ministry of Education, Tianjin, 300130, China.
Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA.
Small. 2023 Jan;19(2):e2205719. doi: 10.1002/smll.202205719. Epub 2022 Nov 14.
Exploiting active and stable non-precious metal electrocatalysts for alkaline hydrogen evolution reaction (HER) at large current density plays a key role in realizing large-scale industrial hydrogen generation. Herein, a self-supported microporous Ni(OH)x/Ni S heterostructure electrocatalyst on nickel foam (Ni(OH)x/Ni S /NF) that possesses super-hydrophilic property through an electrochemical process is rationally designed and fabricated. Benefiting from the super-hydrophilic property, microporous feature, and self-supported structure, the electrocatalyst exhibits an exceptional HER performance at large current density in 1.0 M KOH, only requiring low overpotential of 126, 193, and 238 mV to reach a current density of 100, 500, and 1000 mA cm , respectively, and displaying a long-term durability up to 1000 h, which is among the state-of-the-art non-precious metal electrocatalysts. Combining hard X-rays absorption spectroscopy and first-principles calculation, it also reveals that the strong electronic coupling at the interface of the heterostructure facilitates the dissociation of H O molecular, accelerating the HER kinetics in alkaline electrolyte. This work sheds a light on developing advanced non-precious metal electrocatalysts for industrial hydrogen production by means of constructing a super-hydrophilic microporous heterostructure.
开发在大电流密度下可用于碱性析氢反应 (HER) 的活性和稳定的非贵金属电催化剂，对于实现大规模工业制氢具有关键作用。在此，通过电化学过程合理设计并制备了一种自支撑的泡沫镍负载的具有超亲水性的微孔 Ni(OH)x/Ni S 异质结构电催化剂 (Ni(OH)x/Ni S/NF)。得益于超亲水性、微孔特性和自支撑结构，该电催化剂在 1.0 M KOH 中在大电流密度下表现出优异的 HER 性能，仅需 126、193 和 238 mV 的低过电势即可分别达到 100、500 和 1000 mA cm-2 的电流密度，并且具有长达 1000 h 的长期耐久性，这是最先进的非贵金属电催化剂之一。结合硬 X 射线吸收光谱和第一性原理计算，还揭示了异质结构界面处的强电子耦合有助于 H O 分子的解离，从而加速碱性电解质中的 HER 动力学。这项工作为通过构建超亲水微孔异质结构来开发用于工业制氢的先进非贵金属电催化剂提供了思路。
