Luminescence of CdS and CdS: Cu Quantum Dots Embedded in PVA Matrix

Abstract

We report the synthesis of cadmium sulphide embedded in poly vinyl alcohol (PVA/CdS) and cadmium sulphide doped with copper embedded in poly vinyl alcohol (PVA/CdS: Cu) nanocomposites by chemical route. Characterizations are done by X‐Ray Diffractometer (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), High Resolution TEM (HRTEM), Selected Area Electron Diffraction (SEAD), UV‐Visible (UV‐VIS), Photoluminescence (PL) and Energy Dispersive Spectroscopy (EDS). Sizes of the fabricated nanoparticles obtained from XRD are in good agreement with those from TEM and confinement is found to be strong in some samples. The PL spectra show luminescence from band edge emission as well as from trap levels caused by sulpher vacancies. The PL spectra without as well as with applied DC bias are also studied using platinum electrodes. Results indicate that peak position remains same in the two cases and intensity is an increasing function of excitation voltage. Encouraged by the results obtained so far, which indicates possible applications of the samples as Light Emitting Device, works are being continued to fabricate a nano device with Indium Tin Oxide (ITO) and Aluminum (Al) as electrodes for studying Electro Luminescence spectra.