Development of photoactive material using zinc oxide and photo-corrosion

In this study, ZnO thin films were deposited on ITO (indium tin oxide) coated glass substrate by electrochemical route. Cyclic voltammetry and galvanostatic studies were carried out to determine the suitable potential and current density values.Physical-chemical properties of ZnO films tried to be changed with the help of the deposition parameters. The effect of the deposition parameters on the morphology of ZnO film were characterized by SEM, EDX, XRD and AFM analysis studies. Also, energy band gap values were determined by UV-Vis measurements. In this way, the effect of band gap on the catalytic activity is investigated. With the help of Mott-Schottky analysis, the relationship between electronic properties and deposition parameters are discussed.In order to determine the catalytic efficiency, cyclic voltammetry studies was carried out in a photo electrochemical cell under dark and illuminated conditions by prepared semiconductor electrodes. In addition, Electrochemical Impedance Spectroscopy (EIS) studies were carried out in order to examine the photo-corrosion resistance of obtained ZnO films.At the end of study, all prepared ZnO films are determined that n-type semiconductor characteristics and the band gaps of about 3.3 eV. ZnO films obtained by -0.9 V and -1.1 V deposition potentials for 10 minutes demonstrated better catalytic efficiency. However the stability of this deposit was found not to be good enough, after exposure to UV radiation. Under UV radiation the photo-corrosion of these films take place readily and the efficiency is lost. More negative deposition potential could gave greater particles, exhibit less efficiency and it has lower stability against photo-corrosion is determined.