Chemically grown Bi2MoX6 (X = O, S, and Se) nanostructures for efficient electrochemical hydrogen evolution reaction

Abstract

Here, we present the fabrication of an effective and chemical bath deposition (CBD) of Bi₂MoX₆ (X = O, S, and Se) electrocatalyst for efficient electrochemical hydrogen evolution reaction (HER) activity. To enhance the electrochemical activity of Bi₂MoO₆ (BMO) electrode, the influence of sulfurization and selenization on the wet chemically synthesized BMO has been extensively studied here. These BMO, Bi₂MoS₆ (BMS), and Bi₂MoSe₆ (BMSe) nanostructured developed on nickel-foam are synthesized by a mild two-stage reaction process; a CBD following a sulfo-selenization procedure on BMO. Compared to BMO and BMS electrocatalysts, the BMSe has shown a higher HER activity through a lower overpotential about 120 mV at 10 mA cm⁻² and a lower value of Tafel slope (57 mV dec⁻¹). Surface morphology analysis endows hydrangea flower-type petals, nanosheets, and E. coli bacteria-type surface morphologies for BMO, BMS, and BMSe electrocatalysts, respectively. Thus, this article gives an easy tactic for enhancing the electrochemical HER activity of the BMO through the process of sulfurization/selenization at room temperature (25–27 °C).