Nanoflower-like metallic conductive MoO2 as a high-performance non-precious metal electrocatalyst for the hydrogen evolution reaction

Abstract

Searching for non-precious metal electrocatalysts with high activity and stability for the hydrogen evolution reaction (HER) has attracted considerable attention. Herein, we report the synthesis of nanoflower-like MoO₂ on nickel foam (NFL MoO₂/NF). Remarkably, as a HER electrocatalyst operating in alkaline electrolytes, NFL MoO₂/NF exhibits high stability and activity. The onset potential of NFL MoO₂/NF is almost 0 V versus the reversible hydrogen electrode (RHE) and bubbles can be produced on the surface of NFL MoO₂/NF under a static overpotential of only 10 mV, comparable to commercial Pt/C. NFL MoO₂/NF needs overpotentials of only about 55 and 80 mV to achieve current densities of 10 and 20 mA cm⁻², respectively. NFL MoO₂/NF has superior stability in the long-term electrochemical process and retains 94.3 percent of its initial current density after 25 hours.