Molybdenum-tungsten Oxide Nanowires Rich in Oxygen Vacancies as An Advanced Electrocatalyst for Hydrogen Evolution.

Electrolysis of water is a promising way to produce hydrogen fuel in large scale. The commercialization of this technology requires highly efficient non-noble metal electrocatalysts to decease the energy input for the hydrogen evolution reaction (HER). In this work, a novel nanowire structured molybdenum-tungsten bimetallic oxide (CTAB-D-W4 MoO3 ) is synthesized by a simple hydrothermal method followed with post annealing treatment. The obtained metal oxides feature with enhanced conductivity, rich oxygen vacancies and customized electronic structure. As such, the composite electrocatalyst exhibits excellent electrocatalytic performance for HER in an acidic environment, achieving a large current density of 100 mA cm-2 at overpotential of only 286 mV and a small Tafel slope of 71.2 mV dec-1 . The excellent electrocatalytic HER performance of CTAB-D-W4 MoO3 is attributed to the unique nanowire structure, rich catalytic active sites and promoted electron transfer rate.