Functional Finishing of Cotton Using Titanium Dioxide and Zinc Oxide Nanoparticles

Nanoparticles of TiO₂ and ZnO were chemically synthesized by different routes and were characterized using Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM), X ray diffraction (XRD) and Scanning electron microscopy (SEM). These particles were applied to cotton fabric using 1-10 wt% acrylic binder and cured. The photocatalytic activity of the finished fabric was investigated and a comparison was drawn between the synthesized and commercially available TiO₂ (Degussa P25) sample. Experiments were carried out by exposing the coffee stained samples to solar light. The self-cleaning leading to stain discolouration was quantified from the residual concentration of stain to assess the photoactivity of TiO₂ and ZnO nanoparticles. An attempt was also made to study the effect of concentration of nanoparticles (0.5-1.0 wt% on weight of fabric (owf) and acrylic binder concentration (1, 2, 10 wt% owf) on the self cleaning action. TiO₂ particles with smaller particle size of <10 nm was able to show significantly better activity than the commercial sample. At the same time, finish with nano ZnO though showed a bit lower activity; the self cleaning effect was significant and similar to the commercial TiO₂.