Structural, morphological and optical properties of spray pyrolysis TiO2:GO nano films

Abstract

Thin films of pure and doped nano titanium dioxide (TiO2) were prepared using a chemical pyrolysis technique (CPS), with different nanosize graphene oxide (GO) concentrations in the range (3-9)wt%. The structural, morphological and optical characteristics of these films were investigated. X-ray diffraction (XRD) technique measurements revealed that the structure properties of TiO2 have polycrystalline structure with anatase phase. AFM analysis showed the grain size of TiO2 films with different concentrations was decreased after doping with high concentration of GO ratio. Roughness of these films decreased too after adding of GO impurity for all films from (7.65-5.6)nm except 5wt% percentage where increased to 13.7nm. Optical properties of TiO2 are affected by stimulants of GO, where the refractive index and the real part dielectric constant decrease, while the extinction coefficient and the imaginary dielectric constant increase after continuous addition of GO up to 7wt% and then increases with an increase in the further percentage of impurities. Energy gap values decreased after doping up to 7wt% with GO where the values lies in the range was 3.31 to 3.2eV while arrived to 3.49eV with more increasing of impurity percentage.