Ni and N co-doped MoCx as efficient electrocatalysts for hydrogen evolution reaction at all-pH values

To achieve sustainable production of H-2 fuel through water splitting, noble-metal-free catalysts have been extensively studied for hydrogen evolution reaction (HER), especially molybdenum-based catalysts. Herein, we report the Ni, N-codoped MoCx (Ni-N-MoCx) nanoparticles synthesized from NiMoO4 precursor by oily-solvent-assisted strategy, following the calcination with dicyandiamide. As-obtained Ni-N-MoCx in different magnified SEM images shows grainy structure, MoCx nanoparticles uniformly disperse in carbon substrate. The obtained electrocatalysts can also efficiently electrocatalytic HER in a wide pH value. Ni-N-MoCx shows an onset potential of -74 mV, an overpotential of 163 mV to reach a current density of 10 mA/cm(2) in acid media, an onset potential of -37 mV and overpotential of 124 mV to reach 10 mA/cm(2) in alkaline media. The present study provides some guidelines for preparing the uniformly doped electrocatalysts from multiple compounds with devolatilization characteristics. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.