Investigation of electrocatalytic behavior of mesoporous strontium selenide nanowires for hydrogen evolution reaction

Tremendous efforts have been directed to synthesize electrocatalysts for hydrogen evolution reaction but the electrocatalytic behavior of alkaline metal-based selenides has been rarely reported. Herein, SrSe nanowires have been synthesized using the solvo-hydrothermal process at various temperatures, and the synthesis has been confirmed using different techniques. The employed temperature affects the structure of the strontium selenides and has significantly influenced the hydrogen evolution reaction. Owing to the mesoporous nature and the greater specific and electrochemical surface area, the SrSe nanowires synthesized at 200°C exhibit a greater number of active sites and show an overpotential of 127 mV to approach the current density of 10 mA cm⁻² in 1 M KOH electrolyte. The SrSe nanowires also exhibit a greater turnover frequency of 41.20 ms⁻¹ at the fixed reversible hydrogen electrode potential of 500 mV. The electrocatalyst SrSe nanowires reveal a Tafel slope of 135 mV dec⁻¹, which is better than synthesis at other temperatures. The SrSe nanowires maintained the current density for 24 h chronoamperometry test in 1 M KOH electrolyte. The test results inspire further investigation and indicate the leading potential of SrSe nanowires for hydrogen evolution application.