Synthesis and structural, optical and thermal properties of CdS:Zn2+ nanoparticles

Undoped and Zn (1–5, 10 %) -doped CdS nanoparticles were successfully synthesized by chemical method and polyvinylpyrrolidone was used as capping agent. The morphology and crystalline structure of the samples were studied by transmission electron microscopy and X-ray diffraction. The average particle size of the spherical nanoparticles determined by these techniques was of the order of 2.5–6 nm. The functional groups of the capping agent on CdS:Zn 2+ surface were identified by FT-IR study. The band gap of the nanoparticles was calculated using UV–visible absorption spectra and the result showed that the band gap values were dramatically blue shifted from the bulk CdS. The optimum concentration of the doping ions was selected through absorption study. Photoluminescence of the CdS:Zn 2+ nanoparticle showed strong blue and green emission. The thermal properties of the nanoparticles were analyzed by thermogravimetric-differential thermal analysis.