Characteristics and optical properties of Fe3+ doped SiO2/TiO2 thin films prepared by the sol-gel dip-coating method

Abstract

In this study, we have successfully synthesized Fe3+ doped SiO2/TiO2 thin films on glass substrates using the sol-gel dip-coating method. After synthesizing, the samples were annealed at 5000C in the air for 1 hour. The characteristics and optical properties of Fe3+ doped SiO2/TiO2 films were then investigated by X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FT-IR). An antifogging ability of the glass substrates coated with the fabricated film is investigated and explained by a water contact angle under visible-light. The analyzed results also show that the crystalline phase of TiO2 thin films comprised only the anatase TiO2, but the crystalline size decreased from 8.8 to 5.9 nm. We also observed that the absorption edge of Fe3+- doped SiO2/TiO2 thin films shifted towards longer wavelengths (i.e. red shifted) from 371.7nm to 409.2 nm when the Fe3+-doped concentration increased from 0 to 1 % mol.