Room temperature electrocrystallization of CdSe thin films from ethylene glycol bath

Abstract

Cadmium selenide thin films have been deposited onto stainless steel and fluorine doped tin oxide (FTO) glass substrates by the electrodeposition process, in potentiostatic mode using cadmium acetate and selenium dioxide salts as a precursor sources with ethylenediaminetetraacetic acid (EDTA) tetra sodium salt as a complexing agent. The various preparative parameters such as deposition potential, bath composition, bath temperature, pH of the bath and deposition time have been optimized by photoelectrochemical (PEC) technique. The structural, morphological and optical properties of the deposited films have been studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical absorption techniques, respectively. The X-ray diffraction analysis shows that the films are polycrystalline with hexagonal crystal structure. SEM studies reveal that the grains are uniform with uneven spherically shaped, distributed over the entire surface of the substrates. Optical absorption study shows the presence of direct transition with band gap energy 1.95 eV.