Visible and UV functionality of TiO2 ternary nanocomposites on cotton

This research intends to increase the photocatalytic efficiency of cotton fabrics coated with TiO₂-based nanocomposites under illumination particularly visible light. The fabrics were functionalized using a low-temperature sol-gel method of TiO₂/Metal/SiO₂ nanocomposite systems. Integrating silica and noble metals into TiO₂ sol was put forth for boosting its functionality. Three noble metals (gold (Au), platinum (Pt) and silver (Ag)) with four different concentrations were employed. The photocatalytic activity of the functionalized fabrics was assessed through coffee stain-removal test and photodecomposition of methylene blue (MB) under UV and visible light. The impact of coating layers on fabrics' hydrophilicity was analyzed through measuring the water contact angle as well as the water absorption time. The fabrics were characterized using XRD, SEM and EDS. It was corroborated that the presence of silica enhanced the self-stain-removal capability of fabrics under UV. Moreover, the self-cleaning property of fabrics improved under both UV and visible light after integrating the metals into the colloids. In the same line, the self-cleaning activity threshold of fabrics was shifted to visible region.