Molybdenum disulfide coated nickel-cobalt sulfide with nickel phosphide loading to build hollow core-shell structure for highly efficient photocatalytic hydrogen evolution

A hollow spherical NiCo2S4 photocatalytic material was prepared with a high HER activity in the dye sensitization system. Then the hollow spherical NiCo2S4 was coated by the sheet-shaped 2D MoS2. Through the band gap adjustment, a type-II heterostructure is constructed to move the photogenerated electrons to the outer layer, and part of photogenerated holes migrate to the inner layer, which successfully reduces the degradation rate of the dye sensitizer for slowing down the decay of H2 evolution rate in the dye sensitization system. In addition, Ni2P was used to enrich photogenerated electrons on the outer layer of MoS2 thereby achieving more efficient hydrogen production. The photocatalytic materials were characterized by XRD, SEM, TEM, XPS, UV-vis DRS and N2 Isothermal adsorption experiments. The transfer mechanism of photogenerated carriers was studied by PL, photoelectrochemical tests, and hydroxyl radical capture experiments.