Nanoarchitectonics for synergistic action coupling of Ni nanoparticles with W2C nanowires for highly efficient alkaline hydrogen production.

[Display omitted] • W 2 C nanowires modified with Ni nanoparticles were fabricated as a HER catalyst. • The introduction of Ni nanoparticles can accelerate the water dissociation. • The electronic modulation between W 2 C and Ni can promote hydrogen desorption. • The W 2 C-Ni/CC exhibits excellent HER performance in alkaline electrolytes. Accelerated water dissociation and boosted hydrogen desorption ability are key challenges to improve the kinetics of alkaline hydrogen evolution reaction (HER). Herein, an electrocatalyst consisting of W 2 C nanowires modified by Ni nanoparticles grown on carbon cloth (W 2 C-Ni/CC) is presented. It requires low overpotentials of 37 and 227 mV to drive current densities of 10 and 100 mA cm-2 in 1.0 M KOH, respectively, which not only outperforms most of the W 2 C-based materials that have been reported, but also has catalytic activity comparable to that of commercial Pt/C. The experimental results show a strong synergistic effect between Ni nanoparticles and W 2 C nanowires, with reduced charge transfer resistance and accelerated electron transport in HER process. Further theoretical calculations indicate that the introduction of Ni nanoparticles can significantly accelerate the dissociation of adsorbed water while regulating the position of the W 2 C d-band center, thus weakening the hydrogen adsorption capacity. This work demonstrates that accelerating the dissociation of water and optimizing hydrogen adsorption by introducing metal Ni on the catalyst surface is an effective way to develop efficient catalysts. [ABSTRACT FROM AUTHOR]