Fabrication of PANI@TiO₂ nanocomposite and its sunlight-driven photocatalytic effect on cotton fabrics

Polyaniline (PANI) layer was successfully coated onto titanium dioxide nanoparticles (TiO₂ NPs) through polymerization of aniline under UV light irradiation. Thickness of the PANI layer was controlled by adjusting the aniline amount added in the reaction system. Morphologies of the PANI coated TiO₂ nanocomposite (PANI@TiO₂) were obtained using transmission electron microscope (TEM). The optical properties of the composite nanoparticles were characterized by UV-vis adsorption spectroscopy. Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were also used to analyze the prepared nanocomposites. The PANI@TiO₂ with a thin layer of PANI showed enhanced photocatalytic activity under simulated sunlight. The nanocomposites were coated onto mercerized cotton fabrics to endow the fabrics strong self-cleaning ability under sunlight. Furthermore, the PANI layer renders positive charges to TiO₂ NPs and the mercerization treatment of cotton increases the amount of the hydroxyl groups on the surface, Both of these two factors promote the successful coating of TiO₂ NPs on cotton. These results provide new insight for design of interface interaction between particles and fiber surface. Significantly, the convenient UV induced preparation method of PANI@TiO₂ could achieve an easy scale-up manufacture of photocatalytic materials for functionalization of textiles.