Preparation of cellulose fiber–TiO2 nanobelt–silver nanoparticle hierarchically structured hybrid paper and its photocatalytic and antibacterial properties

Abstract

TiO2 nanobelt-based materials, including TiO2 nanobelts, acid-corroded (AC) TiO2 nanobelts and their silver-loaded products, denoted respectively by Ag/TiO2 nanobelt and Ag/AC TiO2 nanobelt, were used as fillers to prepare cellulose-based composite papers having photocatalytic activity and antibacterial effects. The composition and morphology of the papers, and the valence state of silver in the papers were characterized by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The photocatalytic activity, antibacterial effect of papers and the silver ion release rate of silver-containing composite papers was assessed by degrading methylene blue, checking the inhibition ability to E. coli and monitoring the silver ion concentration with time, respectively. The characterization results indicated that the Ag/TiO2 nanobelt–cellulose composite paper possesses a typical hierarchical structure. TiO2 nanobelt-based nanomaterials adsorb on the surface of cellulose fibers to form organic–inorganic hybrid fiber paper, while silver nanoparticles are assembled on TiO2 nanobelt surface to form metal–oxide composite nanobelts. The photocatalytic activity and cycle stability of the hybrid paper in degrading MO solution are enhanced with increasing the fraction of TiO2 nanobelts. The papers with 40wt% of TiO2 nanobelt exhibit high photocatalytic activity and keep a high value after three photocatalysis cycles. Paper with silver-loaded TiO2 nanobelts, particularly with Ag/AC TiO2 nanobelts, shows good antibacterial effect. This is closely related to the release of silver ion from the paper.