Electrochemical hydrogen evolution reaction (HER) via the splitting of water has required electrocatalysts with cost-effectiveness, environmentally friendliness, high catalytic activity, and superior stability to meet the hydrogen economy in future. In this context, we report the successful synthesis of self-standing mesoporous Ni2P-MoP2 nanorod arrays on nickel foam (Ni2P-MoP2N Rs/3D-NF) through an effective phosphidization of the corresponding NiMoO(4 )NRs/3D-NF. The as-synthesis Ni2P-MoP2 NRs/3D-NF, as an efficient HER electrocatalyst, exhibits small overpotential of 82.2 and 124.7 mV to reach current density of 10 and 50 mA cm(-2), a low Tafel slope of 52.9 mV dec(-1) and it retains its catalytic performance for at least 20 h in alkaline condition. Our work also offers a new strategy in designing and using transition metal phosphide-based 3D nanoarrays catalysts with enhanced catalytic efficiency for mass production of hydrogen fuels. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.