Self-supported tungsten/tungsten dioxide nanowires array as an efficient electrocatalyst in the hydrogen evolution reaction

Abstract

In this study, a tungsten/tungsten dioxide (W/WO₂) nanowires array (NA) was constructed on a carbon paper (CP) (W/WO₂ NA@CP) through the thermal annealing of tungsten trioxide (WO₃) NA. W/WO₂ NA@CP was proven to be an efficient hydrogen evolution cathode with a strong durability in acidic solutions. W/WO₂ NA@CP needs an overpotential of 297 mV to drive a current density of 10 mA cm⁻² and 340 mV to drive a current density of 20 mA cm⁻². The catalytic activity of W/WO₂ NA@CP maintains for at least 50 h in potentiostatic electrolysis. In addition, W/WO₂ NA@CP shows nearly a 100% faradaic efficiency during hydrogen generation. The prominent catalytic activity of W/WO₂ NA@CP correlates with a large number of active sites for the hydrogen evolution reaction and fast electron transport from the CP to W/WO₂ nanowire.