Mixed-solvothermal slow release synthesis of ZnxCd1−xSynanorods with high visible light photocatalytic activities

A mixed-solvothermal method starting from dithizone as a slow release source was developed for synthesizing ZnxCd1−xSy photocatalysts with high visible light photocatalytic activities. XRD, TEM, SEM, XRF, BET, UV-Vis DR, Raman and PL spectra were employed to characterize the crystal phases, morphologies, chemical compositions and optical properties of the obtained products. Interestingly, the released zinc ions could form nanoparticles on the surface of nanorods and the excessive growth of sulfur could bring some new optical properties. The visible light photocatalytic properties of the products were also evaluated by photocurrent measurements in steady state conditions. The results indicated that ZnxCd1−xSy, especially Cd0.78Zn0.22S0.94, exhibited excellent photocatalytic activities, about 10 times higher than the commercial CdS and about 5 times higher than the typical CdS QDs. As a result, a possible mechanism was proposed to explain the formation of the ZnxCd1−xSycatalysts.