Cobalt Molybdenum Oxide Derived High-Performance Electrocatalyst for the Hydrogen Evolution Reaction

The design and synthesis of high-performance hydrogen evolution reaction (HER) catalysts requires an overall consideration of intrinsic activity and number of active sites as well as electric conductivity. We herein report a facile synthesis of a cost-effective catalyst that can simultaneously address these key issues. A cobalt molybdenum oxide hydrate (CoMoO4·nH2O) with a 3D hierarchical nanostructure can be readily grown on nickel foam using a hydrothermal method. Calcination treatment of this precursor material under a reductive atmosphere resulted in the formation of Co nanoparticles on the Co2Mo3O8 surface, which worked in concert to act as active sites for the HER. In addition, the resulting Co2Mo3O8 from the dehydration and reduction reactions of CoMoO4·nH2O showed remarkable increases in both active surface area and electrical conductivity. As a consequence of these favorable attributes, the catalyst exhibited electrocatalytic performance comparable to that of the commercial Pt/C catalyst for the HER in alkaline solution, which is promising for practical water-splitting applications.