Synthesis of 3D-MoO₂ microsphere supported MoSe₂ as an efficient electrocatalyst for hydrogen evolution reaction

Abstract

Many efforts have been devoted to the exploration of non-noble-metal electrocatalysts for the hydrogen evolution reaction (HER) in recent years. Here, we have developed a 3D-MoO₂ microsphere supported MoSe₂ for HER, via a facile hydrothermal approach followed by selenylation treatment. Loosely stacked MoSe₂ layers are formed on the conductive MoO₂ surface, and act as active sites for HER. Meanwhile, the metallic inner MoO₂ facilitates electron transport for proton reduction. In addition, the MoSe₂ could protect the inner MoO₂ from the acidic electrolyte in the HER precess. Significantly, the as-synthesized MoO₂/MoSe₂ exhibits excellent catalytic activity for HER, characterised by a low onset potential of -101 mV vs reversible hydrogen electrode, a small overpotential of 167 mV at a current density of 10 mA cm^-2, along with Tafel slope values of 68 mV dec^-1, as well as outstanding stability in 0.5 mol L^-1 H₂SO₄.