Influence of pH on ZnO films obtained by electrodeposition

Polycrystal ZnO thin films have been deposited on ITO coated glass substrate by the electrodeposition process which is called chronoamperometry, using 0.01 M Zinc nitrate (Zn(NO3)2.6H2O) at 68 ± 2 OC deposition temperature. Applied cathodic potential was selected as to be -1,05 V and aqueous solutions were saturated by oxygen for 30 minutes in all experiments. The influence of different pH values which reaching from 5 to 8 on the morphological and crystal structural ZnO thin films was determined. Thus the optimum deposition conditions have been appointed. The crystal structures were realized by X-ray diffraction (XRD) and consequence demostrate that all the films have a hexagonal grain structure. It was acquired by XRD that the crystallite sizes of the films are between 40nm and 54 nm. The optical properties of the films were analyzed from the absorbance measurements. The energy band gaps of the films ranging between 3.33 eV and 3.62 eV. A scanning electron microscope was used to view the morphological characterization of the obtained films. The results showed that the shape of films is hexagonal pillar form. The another surface was covered very dense rods.