Antibacterial textile and the effect of incident light wavelength on its photocatalytic self-cleaning activity

Wool fabrics with antibacterial and photocatalytic self-cleaning functionalities were developed by applying TiO₂/Pt, TiO₂/Au and TiO₂/Ag colloids to the fabrics surface. This study elucidates how light source type and wavelength range can affect the photo-induced self-cleaning property of the treated fabrics. The self-cleaning activity of fabrics was monitored based on the degradation of coffee stains under UVA (λ_max: 365 nm), visible light (λ_max: 435 nm), full spectrum simulated solar irradiation (λ: 250–800 nm) and filtered simulated solar irradiation (λ: 320–800 nm). In addition, the effect of nanocoatings on the antibacterial activity against Escherichia Coli (E. Coli) bacterium was examined. The incorporated metals synergistically affected the self-cleaning performance, and their efficiency was dependent on the dopants type, concentration, and light sources. It was observed that the filtered simulated sunlight was the most effective light source for inducing self-cleaning without causing any unwanted photo-yellowing damage in wool. Moreover, the coated fabrics containing silver and platinum led to a bactericidal effect, while gold additive did not re-produce this effectiveness.