Synthesis and HER properties of honeycomb Mo2WS6/NF nanorod array solid solution alloys

Abstract

The electrolytic water-based hydrogen production demonstrates exceptional selectivity, minimal environmental impact, and superior purity of the generated hydrogen, thereby presenting promising prospects for a wide range of applications. The scarcity and high cost of Pt-based catalysts for industrial applications necessitate the development of low-cost, stable, and efficient transition metal electrocatalysts for hydrogen electrochemical precipitation (HER). In this paper, Mo2WS6 nanorod array with honeycomb structure was successfully synthesized via one-step hydrothermal vulcanisation of transition metals W and Mo on nickel foam (NF) substrate. The honeycomb nanorod array structure exhibits enhanced specific surface area and abundant active sites, and the well-defined pore structure facilitates the transport of electrolyte and reactive substances. The intrinsic activity of the active sites is significantly enhanced by the synergistic effect of MoS2 and WS2, facilitated by the formation of solid solution alloys. Excellent HER performance (η10=63 mV, η100=183 mV) was demonstrated in alkaline electrolyte (1.0 M KOH) with a corresponding Tafel slope of 93 mV dec−1. Furthermore, Mo2WS6 exhibited excellent stability after undergoing 5000 cycles of charge/discharge and a constant voltage test lasting for 96 hours. This study provides a novel approach for facile synthesis of high-efficiency HER catalysts by a one-step hydrothermal method.