Synthesis of Ni-MOF/Zn_0.5Cd_0.5S and the photocatalytic hydrogen production performance from wastewater

In order to enhance the photocatalytic hydrogen production performance of Zn_0.5Cd_0.5S, Ni-MOF modified Zn_0.5Cd_0.5S composite photocatalyst was prepared by hydrothermal method. The structure and photoelectrochemical properties of the prepared samples were characterized by XRD, SEM, TEM, XPS and other analytical methods. The results show that Zn_0.5Cd_0.5S mainly presents a nano particle structure, and Ni-MOF is mainly composed of ultra-thin square sheets with a length of about 10 µm and a width of about 9 µm. When Ni-MOF is combined with Zn_0.5Cd_0.5S, the Zn_0.5Cd_0.5S nanoparticles deposit on the surface of the Ni-MOF square sheet, and the particle size is significantly reduced, reducing the aggregation of Zn_0.5Cd_0.5S nanoparticles. In addition, there is a blue shift in the light absorption range for the composite, but still excellent visible light response ability. In the landfill leachate mixed shale gas flowback wastewater, the 15% Ni-MOF/Zn_0.5Cd_0.5S shows the best photocatalytic hydrogen production performance. Under simulated sunlight, the hydrogen production after 3 h of illumination is up to 1887 µmol. The hydrogen production process satisfies the zero-level reaction, with a hydrogen production rate of 685.9 µmol/h, which is approximately 5.7 times as high as the hydrogen production rate of Zn_0.5Cd_0.5S.