A flower-like MoS2 with a stepped edge structure was successfully and controllably fabricated as a bifunctional electrocatalyst efficient for hydrogen and oxygen evolution reactions. The hierarchically porous polycrystalline MoS2 was characterized by a combination analysis of XRD, Raman, XPS, N-2-BET, SEM and TEM. In the hydrogen evolution reaction (HER), this as-obtained MoS2/Ni catalyst presents significantly enhanced performance versus most previously studied catalysts. In the oxygen evolution reaction (OER), the electrocatalyst MoS2/Ni gives rise to a rather low overpotential of similar to 0.335 V at 20.0 mA cm(-2) and much enhanced durability over 6 h. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.