Synthesis of TiO₂&SiO₂ nanoparticles as efficient UV absorbers and their application on wool

Uniform core-shell structured TiO₂&SiO₂ nanoparticles (NPs) were fabricated by synthesizing TiO₂ NPs, which were then coated with shells of SiO₂. The structure and optical properties of TiO₂&SiO₂ NPs were characterized with a transmission electron microscope and a UV/Vis spectrophotometer. The photocatalysis was evaluated by photodegradation of rhodamine B. TiO₂&SiO₂ NPs were coated onto wool fabrics to improve their photostability. The treated wool fabrics were characterized using scanning electron microscopy. Photoyellowing of treated wool fabrics after exposure to simulated sunlight was evaluated using a Datacolor Spectraflash spectrophotometer. At an application level of 5% o.w.f. of the composite nanoparticles, the treated wool fabrics exhibited considerable photostability. Polydimethylsiloxane was applied as an after-treatment, which provides good fastness to washing. This simple but effective coating could be useful for the development of UV protection methods for various substrates.