Self-cleaning, anti-fogging and aseptic thin films based on photocatalytic and superhydrophilic properties of TiO2, have been used for commercial purposes worldwide for decades. TiO2 is a commercially available natural material with semiconducting characteristics, with two main disadvantages referring to self-cleaning thin films applications: (1.) wide bandgap (3,2 eV for anatase) with absorption in UV spectral region, representing less than 5% of sunlight and (2.) fast recombination of pairs electron-hole, produced by photon interaction. Doping with elements is one of methods which improves these disadvantages, and vanadium may be suitable dopant.
In this work, TiO2-SiO2 thin films with different amounts of vanadium dopant were prepared by sol-gel synthesis and dip-coated on different substrates. We used different techniques for structural, optical and photocatalytic characterisation (UV-Vis, IR and Raman spectroscopy, SEM, XRD, Contact angle measurements …).
Despite low temperature preparation TiO2-SiO2 thin films all were transparent and showed excellent photocatalytic properties. XRD, Raman and IR spectroscopy showed possible incorporation of vanadium into TiO2-SiO2 structure. UV-Vis spectroscopy results showed that transparency, spectral reflectance and haze do not change significantly with adding vanadium dopant. It brought no specific improvements in optical, structural or photochemical characteristics. However, optical properties promised good photocatalytic results. Due to Coronavirus pandemic (March–June 2020) we could not perform all scheduled photocatalytic experiments.
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