N-Doped Carbon-Coated Tungsten Oxynitride Nanowire Arrays for Highly Efficient Electrochemical Hydrogen Evolution

Graphical Who WON the race? N-Doped carbon-coated tungsten oxynitride nanowire arrays on carbon cloth (WON@NC NAs/CC) are prepared by annealing the WO 3 NAs/CC precursor under an Ar atmosphere in the presence of dicyandiamide and are used as a 3 D hydrogen evolution cathode with superior activity and stability over the pH 0–14 range. PBS=phosphate-buffered saline, RHE=reversible hydrogen electrode. It is highly desired but still challenging to develop active nonprecious metal hydrogen evolution reaction (HER) electrocatalysts operating under all pH conditions. Herein, the development of three-dimensional N-doped carbon-coated tungsten oxynitride nanowire arrays on carbon cloth as a highly efficient and durable HER cathode was explored. The material delivers current densities of 10 and 100 mA cm −2 at overpotentials of 106 and 172 mV, respectively, in acidic medium, and it also performs well in neutral and basic electrolytes.