Hydrophilic, self-clean and anti-fog SiO۲-TiO۲ thin film photocatalyst under visible light irradiation

Silicon dioxide-titanium dioxide (SiO۲-TiO۲) thin films with super-hydrophilic properties and photocatalytic activity were deposited on the glass substrates by a simple dip-coating method. Morphological, structural and optical properties of the SiO۲-TiO۲ thin films were characterized using Field Emission Scanning Electron Microscopy (FE-SEM), X-Ray Diffraction (XRD) patterns, and UV-Vis spectroscopy. The XRD patterns indicate decrease in the crystallite size from ۵۱.۰ nm to ۲۲.۷ nm with addition of SiO۲ to the TiO۲ structure. Moreover, the estimated band gap from optical measurements has a reduction from ۳.۱۳ eV to ۲.۶۳ eV for the SiO۲-TiO۲ sample. Water Contact Angle (WCA) measurements showed that SiO۲-TiO۲ thin film has super-hydrophilic property and self-cleaning, rainproof, anti-fog properties which can be effectively controlled by visible light illumination. An improved photocatalytic performance compared to TiO۲ in terms of higher efficiency (~۱۰۰%) in degradation of methylene blue (MB) pollutant under visible light was achieved.

کلیدواژه ها:

SiO۲-TiO۲ ، Thin film ، photo-catalyst ، super-hydrophilic ، visible light