Self-standing, hybrid three-dimensional-porous MoS2/Ni3S2 foam electrocatalyst for hydrogen evolution reaction in alkaline medium

Self-standing and hybrid MoS2/Ni3S2 foam is fabricated as electrocatalyst for hydrogen evolution reaction (HER) in alkaline medium. The Ni3S2 foam with a unique surface morphology results from the sulfurization of Ni foam showing a truncated-hexagonal stacked sheets morphology. A simple dip coating of MoS2 on the sulfurized Ni foam results in the formation of self-standing and hybrid electrocatalyst. The electrocatalytic HER performance was evaluated using the standard three-electrode setup in the de-aerated 1 M KOH solution. The electrocatalyst shows an overpotential of 190 mV at -10 mA/cm(2) with a Tafel slope of 65.6 mV/dec. An increased surface roughness originated from the unique morphology enhances the HER performance of the electrocatalyst. A density functional approach shows that, the hybrid MoS2/Ni3S2 heterostructure synergistically favors the hydrogen adsorption-desorption steps. The hybrid electrocatalyst shows an excellent stability under the HER condition for 12 h without any performance degradation. (c) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.