Spatially segregated sites on Mo/V-dual-tailored Ru metallic glass nanosheets accelerate alkaline hydrogen evolution
Fenyang Tian, Tongbo Zhang, Menggang Li, Longyu Qiu, Fengyu Wu, Sheng Zeng, Lin He, Tianci Wei, Jie Sheng, Shuo Geng, Weiwei Yang, Yongsheng Yu
Abstract
Abstract Alkaline hydrogen evolution reaction (HER) is a cornerstone for efficient green hydrogen production via anion exchange membrane water electrolysis (AEMWE), yet suffering from sluggish water dissociation kinetics. Ruthenium (Ru)-based catalysts exhibit Pt-like activity at a fraction of the cost, but their performance is hampered by excessive hydroxide accumulation on Ru sites, a consequence of their overly strong oxygen affinity and suboptimal d-band center. Herein, we reported a class of Mo/V-dual-tailored Ru metallic glass nanosheets (Mo/V-Ru NSs) to enable spatial segregation of water dissociation sites (on Mo/V) from hydrogen evolution sites (on Ru), achieving the acceleration of alkaline HER electrocatalysis. The optimized Mo/V-Ru NSs deliver outstanding alkaline HER performance, with overpotentials of 36 and 86 mV at 10 and 100 mA·cm−2, respectively, outperforming pure Ru counterparts and commercial Pt/C. Remarkably, the Mo/V-Ru NSs-based AEMWE can achieve a high current density of 100 mA·cm−2 at a low cell voltage of 1.68 V and exhibit excellent durability for over 120 h. In-situ Fourier transform infrared (FT-IR) spectroscopy elucidates the role of Mo and V in water adsorption and O–H bond cleavage, synergistically lowering the water dissociation barrier. Density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations confirm enhanced water adsorption on Mo/V sites and preferential Ru-H coordination, supporting the site-segregation mechanism.