Low temperature method for synthesis of ZnS quantum dots and its luminescence characterization studies

Zinc Sulfide (ZnS) quantum dots of sizes 2.68–4.8 nm, embedded on polyvinyl alcohol (PVA) matrix, have been synthesized at 70° C by wet chemical method. X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), UV–vis spectroscopy and photoluminescence (PL) Spectroscopy has been adopted for sample characterization. Optical absorption spectra showed strong blue shift, which is an indication of strong quantum confinement. Photoluminescence spectra of the sample have been recorded at room temperature and observed two peaks centred around 415 nm and 440 nm. We have assigned the first peak due to band gap transitions while the later due to sulfur vacancy in the sample.