Hexagonal NiMoO4-MoS2 nanosheet heterostructure as a bifunctional electrocatalyst for urea oxidation assisted overall water electrolysis

For overall water splitting, easy synthesis methodologies for non-precious metal bifunctional electrocatalysts with the advantages of low cost and high activity are essential. Herein, a hexagonal NiMoO4-MoS2 nanosheet heterostructure on nickel foam (NiMoO4-MoS2/NF) was synthesized by simple hydrothermal and annealing treatment. Synergies between NiMoO4 and MoS2 significantly promoted the intrinsic activity of the HER and exposed more active sites for the UOR and the HER. The NiMoO4-MoS2/NF electrocatalyst shows small electric potentials of 1.345 V for the UOR and 23 mV for the HER in 1.0 M KOH with 0.5 M urea at 10 mA cm(-2). NiMoO4-MoS2/NF has outstanding overall water splitting performance, with a low cell voltage of 1.445 V at 10 mA cm(-2) and an excellent sustainability of 24 h. The bifunctional electrocatalyst's design strategy and controllable synthesis of the hexagonal NiMoO4-MoS2 nanosheet heterostructure will benefit the overall urea water separation efficiency.

Automated summary

In this study, a hexagonal NiMoO4-MoS2 nanosheet heterostructure was synthesized, which showed excellent performance and sustainability in overall water splitting. The synergies between NiMoO4 and MoS2 improved the intrinsic activity of the electrocatalyst and exposed more active sites.