In situ Construction of Free-Standing High-Performance Ni-Based Dual Intermetallic Composites for Alkaline Hydrogen Evolution
Xu Wang, Quan Li, Shuzhao Feng, Yanru Liu, Caixia Xu, Qiuxia Zhou, Hong Liu, Qingyu Yan
Abstract
Abstract Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production. However, the initial hydrolysis dissociation in alkaline media impedes the hydrogen evolution reaction (HER) kinetics of commercial catalysts. To overcome this limitation, this study focuses on the development of a highly efficient electrocatalyst for alkaline HER. Ni-based intermetallic compounds exhibit remarkable catalytic activity for HER, with the NiMo alloy being among the most active catalysts in alkaline environments. Here, we designed and fabricated self-supported multiscale porous NiZn/NiMo intermetallic compounds on a metal foam substrate using a versatile dealloying method. The resulting electrode exhibits excellent HER activity, achieving an overpotential of just 204 mV at 1000 mA/cm 2 , and demonstrates robust long-term catalytic stability, maintaining performance at 100 mA/cm 2 for 400 h in an alkaline electrolyte. These findings underscore the potential of nanosized intermetallic compounds fabricated via a dealloying approach to deliver exceptional catalytic performance for alkaline water electrolysis. Graphical Abstract The NiZn/NiMo double intermetallic composite is fabricated via a versatile dealloying route. Leveraging the high intrinsic activity of the intermetallic and the increased density of active sites provided by multiscale porous architecture, the resulting NiZn/NiMo electrode exhibits significantly lower overpotential and long-term catalytic stability toward alkaline HER. The intermetallic electrode demonstrates unique intrinsic catalytic activity for HER and exceptional corrosion resistance.