Carboxymethyl chitosan coating to block photocatalytic activity of TiO^sub 2^ nanoparticles

摘要

In order to lower photocatalytic degradation of TiO^sub 2^ on skin and textiles, carboxymethyl chitosan (CMCH) was used to coat TiO^sub 2^ nanoparticles. The polymer (CMCH) not only acted as the blocking agent of photocatalytic activity, but also dispersed TiO^sub 2^ nanoparticles better to prohibit them from congregation by anchoring them. The structure of as-prepared nanocomposites was characterized by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The TiO^sub 2^/CMCH nanocomposites were coated onto cotton fabrics by a dip-pad-drycure process. The treated cotton fabrics demonstrated lower photocatalytic activity in comparison to cotton fabrics treated by pure TiO^sub 2^ in a typical photocatalytic test. The treated cotton showed a combination of bactericidal activity of TiO^sub 2^ and CMCH, and excellent protection against UV radiation.