Three-dimensional bacterial cellulose/polydopamine/TiO2 nanocomposite membrane with enhanced adsorption and photocatalytic degradation for dyes under ultraviolet-visible irradiation.

Cleaner production of photocatalyst with efficient property and stable reusability is of great importance for the elimination of organic pollutants in wastewater. Herein, we present a bacterial cellulose (BC)-based nanocomposite membrane with enhanced adsorption and photocatalytic degradation for dyes under UV radiation, by using BC nanofibers as a three-dimensional soft template, coated with the polydoamine (PDA) as a functional layer and a protective agent for immobilization of titanium dioxide (TiO2) nanoparticles. Compared with commercial P25, the as-prepared BC/PDA/TiO2 composite presented higher adsorption capacity for methyl orange, Rhodamine B and methylene blue, and the photocatalytic properties within 30 min after irradiation were further improved. BC/PDA/TiO2 also showed good stability, proved by the 5.5% reduction in photocatalytic capability after five cyclic tests. We expect our design could provide a facile and green approach with excellent photo-degradation performance for organic pollutants, providing further applications for photocatalysis and wastewater treatment.