Preparation And Photocatalytic Properties Of MoS₂/CuS,ZnS/CuS Nanocomposites

Based on the excellent optical and electrical properties of copper sulfide nanomaterial,semiconductor heterojunction II type photocatalysts were constructed by a two-step hydrothermal method.The photocatalysts not only can effectively degrade organic pollutants,but also has the efficient photocatalytic reduction the excellent properties of inorganic pollutants.MoS2/CuS composite with stable three-dimensional flower-like structure was obtained by modulating the morphology of the composition of the composite materias The composite material phase was pure,free of any impurities,and the heterojunction structure could be clearly observed under high resolution transmission electron microscopy.By characterizing the optical properties of the composite material,it is found that the composite material not only has a wide spectral response characteristic,but also a much higher separation efficiency than a single component material.Methylene blue solution and potassium dichromate solution were selected as indicators of photocatalytic oxidative degradation and photocatalytic reduction reaction,respectively.The study found that MoS2/CuS composites compared with single component material not only have better photocatalytic oxidation ability(degradation rate of 20 mg/L methylene blue solution within 50 min is 78.2%),and also have considerable photocatalytic reduction activity(degradation rate of 40 mg/L potassium dichromate solution within 40 min is 93.3%).In addition,ZnS/CuS semiconductor heterojunction composites were also prepared by hydrothermal synthesis.The composites were characterized by XRD,SEM,TEM,XPS,PL and UV-Vis,indicating that the material phase was pure,the lattice was ordered.The heterostructure provided an effective spatial separation path for the photogenerated electron-hole pairs of the composite,and the material had a visible light response.The photocatalytic performance test showed that the composite also had good photocatalytic activity.Among these samples,2ZC had the best performance and the photocatalytic oxidation degradation rate of methylene blue solution is 86.1%within 50 min.It is worth noting that the photocatalytic reduction rate of Cr(VI)is 96.4%within 6 min.Finally,it was found that the photocatalytic performance of the samples did not change significantly,showing good stability after five tests of repeatability.