Sol-gel derived titanium dioxide finishing of cotton fabric for self cleaning

Abstract

Nano- TiO₂ coatings have been applied to cotton fabric by sol-gel process without any crosslinker or binder. The characteristics of coatings derived from two different approaches by sol-gel process are compared. It is revealed from the Fourier transform infrared spectroscopy that the TiO₂ sol particles have the similar spectra as observed for commercial TiO₂ (Degussa P25). The nano-TiO₂ particles are applied to cotton fabric using 1 wt% acrylic binder and cured. The photo-catalytic activity of the finished fabric has been investigated and a comparison is made between the commercially available TiO₂ sample and the nano-sol coated samples. The self-cleaning action of nano-crystalline TiO₂ coated cotton has been quantified by measuring the photo-catalytic degradation of stain due to visible light irradiation. Nano-sol derived TiO₂ particles with smaller particle size of <10 nm (prepared using nitric acid) show significantly better activity than the commercial TiO₂ sample of the particle size 25nm. The titanium coatings on fabric also act as anti-bacterial photocatalyst.