Construction of Ag–ZnO/cellulose nanocomposites via tunable cellulose size for improving photocatalytic performance

The Ag–ZnO/cellulose nanocomposites with tunable structure and properties was fabricated and used as an effective photocatalyst for degrading methyl orange (MO) dye. The structure and properties of the Ag–ZnO/cellulose nanocomposites were regulated by the cellulose fiber size via different times of grinding treatment. The morphologies of ZnO NPs changed from flower-like to flaky with the decrease of diameter of cellulose fiber from 130 nm to 42 nm, and loading amounts of ZnO and Ag NPs on photocatalyst increased from 56.12% to 57.46% and 5.28%–6.54% respectively. The finer fibrils provided a more uniform network compared with coarse fibers, which is benefit for stable distribution of ZnO and Ag nanoparticles (NPs) and facile separation from wastewater. The Ag–ZnO/cellulose nanocomposites, prepared from cellulose fiber with grinding treatment of 30 times, exhibited homogeneous three-dimensional cellulose network with specific surface area of 40.64 m2/g and possessed excellent photocatalytic activities and reusability for MO degradation. This work provided a novel approach to control the morphology of ZnO by tuning cellulose size, for improving photocatalytic activities and recovery efficiency of Ag–ZnO/cellulose nanocomposites.