Fe-doping effect on the photoelectrochemical properties enhancement of ZnO films

In this study, undoped and Fe doped nanostructured Zinc oxide thin films were synthesized by simple and low cost co-precipitation and spin-coating technique. Surface morphology and crystalline structure of the deposited films were investigated by Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) techniques. XRD analysis demonstrated that the films were polycrystalline with the hexagonal phase. From SEM investigations, the surface morphology of the deposited films was found to depend on Fe concentration. The obtained optical measurements indicated that Fe doping decreases the optical transmission and shift the optical gap to 3.08 eV for 0.5 at.% Fe content. An optimum Fe concentration of 0.5 at.% was found to lead to the highest photoconduction sensitivity of the ZnO films. The photocurrent enhancement response was explained by a better charge separation and collection efficiency under visible light illumination.