Electrochemically synthesized MoS2 with enhanced S-bonds for hydrogen evolution

Low-cost, highly active, and robust electrocatalysts are needed for more efficient H 2 production from water splitting, herein, we present an amorphous MoS 2 -Ni 3 S 2 heterostructure on the nickel foam (NF) substrate via a facile hydrothermal treatment and a one-step electrodeposition approach. The S 2 2 - sites in the fabricated electrocatalyst could be conveniently modulated by synthesis conditions. The optimized amorphous MoS 2 -Ni 3 S 2 @NF-24 shows an excellent electrocatalytic activity for HER with the overpotential of 58 mV at 10 mA cm −2 and stabilizes for over 50 h when used as a bifunctional catalyst for overall water splitting in 1 M KOH electrolyte at room temperature. Experimental characterizations and DFT calculations demonstrate that the excellent electrocatalytic performance of the fabricated heterostructure could be attributed to the synergistic effect of the proper hydrogen binding free energies of MoS 2 with abundant bridging S 2 2 - and the strong adsorption of OH − to the Ni 3 S 2 . This work proposed a finely designed MoS 2 -based hybrid catalyst for efficient alkaline HER, thus providing insights into the design and fabrication of inexpensive electrocatalysts for wide range of applications.