This paper describes photocatalytic cotton fibers produced by a TiO2 nanoparticle self-assembly process with the assistance of carboxylic groups. The carboxylic group was introduced by a displacement reaction, the molecular structure of the glucose unit was studied by utilizing solid C-13 NMR. The appearance of the prepared fibers was observed by scanning electron microscopy, it was found that nano-TiO2 coated uniformly on the fiber surface. The loading amount of nano-TiO2 was depended on the displacement degree of C-6-OH. UV-Vis experiments showed these coated fibers undergo photocatalysis efficiently. The degradation reaction of Rhodamine 6G under UV light obeys the zero-order rate law. (C) 2012 Elsevier Ltd. All rights reserved.