CdSe ve CdSe/ZnO Filmlerin Elektrokimyasal Sentezi: Morfolojik, Yapısal ve Elektronik Özellikler

Abstract

CdSe films were electrochemically prepared on ITO electrode in aqueous solution applying a constant potential. Structural, morphological and optical features of CdSe thin films were examined with FE-SEM, XRD and UV-visible spectrophotometry techniques. XRD results revealed CdSe films were deposited, in the form of cubic crystals from aqueous solution of Cd2+ and Se4+, in presence of Na2SO4 supporting electrolyte. Band gap values of CdSe films were found between 1.88 and 2.0 eV. Wide band gap ZnO was electrochemically deposited on narrow band gap CdSe to improve its optoelectronic properties. Band gap value of CdSe/ZnO nanonorods was determined as 2.7 eV. Mott-Schottky equation was utilized to calculate flat band potential (EFB), as well as charge carrier density (ND) of materials. ND values were found as 1.623×1020 and 9.186×1020 cm-3 for CdSe and CdSe/ZnO, respectively. ZnO offers higher stability and lower band gap is promising material to be utilized in solar cell applications.