Cadmium complexes based on Xanthate and dithiocarbamate such as [Cd(ethyl xanthate)2], [Cd(morpholine-4-dithiocarbamate)2] and [Cd(piperazine1-dithiocarbamate)2] have been used as efficient single source precursors. The formation of CdS nanostructures have been achieved by solvothermal route of synthesis. Crystallographic and morphological characterization of synthesized nanomaterials has been done by X-ray diffraction (XRD) and electron microscopy [Transmission Electron Microscope (TEM)], respectively. Diffraction and electron microscope studies reveal the formation of wurtzite structured CdS nanostructures of various morphologies (nanorods and nanospheres). UV–vis absorption and Fourier transform infrared (FTIR) spectroscopic studies have been carried for the detailed optical as well as qualitative analyses. It has been reported that the morphology of synthesized nanomaterials strongly depends upon the type of the precursor complexes. Photo-catalytic activity of the synthesized nanostructures has been tested in visible irradiation using methylene blue (MB) dye as a test contaminant in aqueous media. Morphology dependent photo-catalytic activity of the synthesized nanomaterials has been studied in detail to explore the potential of prepared nanostructures to purify polluted water.