Laser-assisted coupling of nitrogen-doped carbon-coated molybdenum/molybdenum dioxide rods for efficient pH-universal hydrogen evolution electrocatalysis

Herein, a simple and fast laser-assisted coupling method is used for preparation of rod-like carbon-coated Mo/MoO2 hybrids at room temperature and air environment. Under high energy of laser and reductive atmosphere caused by precursor decomposition, Mo-polydopamine complex-wrapped MoO3 rods are quickly converted into nitrogen-doped carbon-coated Mo/MoO2 rods. Carbon-coated Mo/MoO2 exhibits high surface area, uniform metal dispersion and appealing hydrogen evolution reaction (HER) catalytic performance in a wide pH range. Carbon-coated Mo/MoO2 shows overpotential of 134, 108 and 164 mV to deliver current density of 10 mA cm(-2) under alkaline, acidic and neutral solution, respectively. Theoretical calculation demonstrates that combination of Mo and MoO2 into Mo/MoO2 composite favors the dissociation of water and adsorption of hydrogen. This study not only provides a high-efficiency strategy for preparation of electrocatalysts but also give guidance for development of hybrid electrocatalysts for HER. (C) 2021 Elsevier Inc. All rights reserved.