SiO2-modified TiO2 nanostructure for solar panel coatings: Enhanced photocatalytic and self-cleaning surface applications

Abstract

In this study, SiO2-modifiedTiO2 thin films were successfully deposited on glass substrates for solar photocatalytic applications. The films were coated using the spin-coating method and subsequently annealed at 500 °C and 600 °C. The incorporation of amorphous SiO2 acts as a structural modifier, promoting the transformation of TiO2 from the rutile to the anatase phase. XRD results confirmed
enhanced crystallinity and phase purity at higher annealing temperatures, while AFM analysis revealed that grain growth and surface smoothness improved significantly at 600 °C. Optical studies showed that the bandgap increased slightly with annealing temperature due to improved crystallinity, while PL spectroscopy highlighted reduced non-radiative recombination at higher temperatures. Furthermore, the addition of SiO2 lowered the contact angle, improving the surface wettability. The photocatalytic activity, evaluated by methyl orange degradation, showed improved performance for the 33% SiO2 sample annealed at 500 °C, achieving 55.48% degradation after 90 minutes under sunlight. This was attributed to an optimal balance between the crystallinity, defect structure, and surface area. The findings demonstrate that modifying TiO2 with SiO2 and optimizing the thermal treatment significantly enhances
its photocatalytic performance, making these films promising candidates for environmental and solardriven applications.