Hierarchical Heterostructured Mo2C/Mo3Co3C Bouquet-like Nanowire Arrays: An Efficient Electrocatalyst for Hydrogen Evolution Reaction

Multiple active constituents of heterostructured catalysts could form moderate hydrogen binding strength on the surface, which is expected to solve the inefficient issue of hydrogen evolution reaction (HER). Herein, hydrothermal followed by carbon deposition treatment is introduced to design hierarchical heterostructured Mo2C/Mo3Co3C bouquet-like nanowire arrays on Ni foam (Mo2C/Mo3Co3C-NF), and bring abundant Mo2C-Mo3Co3C interfaces for synergetic electrocatalysis. The addition of Co modifies the electronic structure of the resultant catalysts, and the HER intrinsic activity has been remarkably promoted. Additionally, the 3D Ni foam acts as a current collector that facilitates the directional growth of the active phases, and the exposure of more active sites for hydrogen evolution reaction. As expected, the Mo2C/Mo3Co3C-NF-2 (the molar ratio of Co/Mo is 2/4) catalyst electrode exhibits a low onset overpotential of 24 mV and achieves an overpotential of 87 mV at the current density of 10 mA cm–2 in 1 M KO...