Cu doped MoS2 nanosheets/NiS2 nanowires heterogeneous structure for enhanced hydrogen evolution reaction

Developing highly efficient, affordable and renewable electrocatalysts is greatly important for large-scale pro-duction of hydrogen. MoS2 has been regarded as a promising electrocatalyst for hydrogen evolution reaction (HER). Foreign atom doping and forming heterogeneous structure have been proved to be the efficient ways to improve its electrocatalytic performance. In this paper, Cu doped MoS2 nanosheets supported on NiS2 (Cu-MoS2/ NiS2) nanowires are prepared via the electrospinning, sulfuration and subsequent hydrothermal process. Benefitting from the heterointerfaces and foreign Cu atoms doping, the as-synthesized Cu-MoS2/NiS2 hybrid nanowires possess more electrocatalytic active sites and a favorable synergistic effect compared to the MoS2 nanoflowers, NiS2 nanowires and MoS2/NiS2 hybrid structure. The Cu-MoS2/NiS2 hybrid nanowires exhibit an excellent HER performance with a low overpotential of 56 mV (105 mV) at 10 mA/cm2 and a small Tafel slope of 49 mV/dec (59 mV/dec) in 0.5 M H2SO4 (1 M KOH). It is a potential substitute for noble metal electrocatalysts in the future.