Hydrophilic of SiO2/TiO2 double layers thin film prepared by sol-gel dip coating method

In this study, TiO₂, SiO₂ and SiO₂/TiO₂ double layers thin films were prepared and coated on the glass plate via sol-gel dip coating method. The samples were characterized using X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) to analyze the present of TiO₂ and SiO₂ compounds in the prepared samples. Meanwhile, UV-Vis spectrophotometer was used to measure the transmittance spectra of the thin films and the water contact angle was analyzed to determine the hydrophilic properties. XRD result revealed that the TiO₂ xerogel was anatase phase after the calcination. As for SiO₂ xerogel, the pattern of IR spectra demonstrated the formation of SiO₂ network. Therefore, from these results, the TiO₂ and SiO₂ xerogels were successfully prepared. Besides that, surface morphology of prepared coating films were studied using Scanning Electron Microscopy (SEM). As expected for SiO₂/TiO₂ double layers thin film, SiO₂ particles aggregates were randomly distributed on the surface of TiO₂. Performance wise, the prepared coating samples were also shown a positive result of water contact angle analyses. This finding revealed that a SiO₂/TiO₂ double layers thin film has demonstrated hydrophilic property based on the 13.9° of contact angle achieved. Moreover, the light transmittance of this thin film at normally incident light can be reached up to 70%. Therefore, it can be summarized that SiO₂/TiO₂ double layers thin film demonstrated a hydrophilic surface in nature.