Photocatalytic self-cleaning textiles based on nanocrystalline titanium dioxide

The anatase TiO ₂ in this study was prepared in an aqueous solution through a sol-gel process with a small amount of acid, which prevented the loss of the mechanical strength of the cotton fabrics when compared with previous methods. The application of the anatase TiO ₂ to textiles, which formed a transparent, thin film of nanocrystalline TiO ₂ on the fiber surface, was done via a simple dip-pad—dry-cure process. The adhesion between the TiO ₂ thin film and the cotton substrates was high, indicated by good fastness at 20 home launderings. The bending rigidity was increased by 13% and the air permeability was reduced by 0.76% after TiO ₂ treatment, which indicated that the treatment did not significantly influence the fabric handling and the air permeability. The mechanical strengths of the treated cotton fabrics investigated indicated that the photocatalytic decomposition of the cellulosic chains of the cotton fibers is very limited after 20 h of irradiation.