Superhydrophilic self-cleaning cotton fabric with enhanced antibacterial and UV protection properties

Abstract

A multifunctional cotton fabric with superior photocatalytic self-cleaning, antibacterial activity and UV protection was prepared through treatment with TiO2/Pt/SiO2 colloid, clarifying the influence of coating formulation on these functionalities. The photocatalytic activity of coated fabrics under UV and white-fluorescent light was tested and synergistic effects of Pt and silica in enhancing the self-cleaning property of fabrics were demonstrated. Various molar ratios of Pt:Ti (0.01%, 0.1%, 0.5%, and 1%) and Ti:Si (50/50 and 30/70) were utilised in synthesising the colloids. The self-cleaning performance of fabrics was assessed through monitoring coffee stain removal efficiency and methylene blue (MB) dye degradation kinetics. The results demonstrated an effective photocatalytic self-cleaning property on fabrics coated with TiO2/Pt/SiO2 colloids. Increasing the concentrations of Pt and silica both contributed to enhancing the self-cleaning property. The fabric coated with ternary TiO2/Pt/SiO2 30/1/70 colloid resulted in 43.5% higher MB dye removal compared with pure TiO2 after 3h irradiation under visible light. Moreover, the fabrics containing Pt 1% dopant possessed excellent bactericidal activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria, regardless of the presence of silica. While the addition of silica slightly reduced the UV protection of coated fabrics, increasing the concentration of Pt to 1% increased the protection level to 45 + . Various characterisation techniques including SEM, XPS, XRD, and TEM were employed to study the Pt-doping of TiO2 nanoparticles, as well as the effect of Pt concentration, superhydrophilicity of silica, and the chemical composition of coatings on the functionalities of fabrics.