Promotion of the excited electron transfer over Ni- and Co -sulfide co-doped g-C3N4 photocatalyst (g-C3N4/NixCo1-xS2) for hydrogen Production under visible light irradiation

A Ni- and Co-sulfide co-doped g-C3N4 photocatalyst (g-C3N4/NixCo1-xS2) was prepared by hydrothermal method and this photocatalyst, namely, g-C3N4/NixCo1-xS2 shown excellent photocatalytic properties due to the special structure of Ni-Co-S with boundary different exposure to active site of transition metal-metal (Ni-Co) active planes. With the introduction of Co atoms, the H-2 production amount reached the maximum about 400.81 mu mol under continuous visible light irradiation for 4 hours based on the efficiently charge separation and greatly improved electron transfer resulted from the presence of sufficient active exposure at the boundary. The serial studies shown that the existence of Ni-Co-S structure over g-C3N4 active surface is the key factor of activity affections by means of several characterizations such as SEM, XRD, XPS diffuse reflectance etc. and the results of which were in good agreement with each other. A possible reaction mechanism over eosin Y-sensitized g-C3N4/NixCo1-xS2 photocatalyst under visible light irradiation was proposed.