Boosting the recyclability of flame-made Bi2O3 via insitu immobilization in cellulose acetate nanofibers for efficient photocatalytic degradation of rhodamine B dye

Flame spray pyrolysis is a novel fast-process for producing functional metal oxides. However, these functional nanomaterials are challenged with poor recyclability in water treatment from pollutants such as dyes. Herein, Bi2O3 nanoparticles were produced by flame spray pyrolysis and spun together with eco-friendly cellulose acetate polymer into nanofiber membrane via electrospinning technique. The results reveal that cellulose acetate (CA) has good interaction with the particles, leading to reduced band gap, retardation of fast recombination of carriers and good electron transportation on the surface of the nanofiber membrane. The Bi2O3/CA nanofiber membrane records similar photocatalytic performance to that of flame-made Bi2O3 nanoparticles, that is about 95% dye degradation at 90 min, which was far better than CA and Bi2O3/polyacrylonitrile nanofiber membranes. The electron spin resonance test and free radical scavenger test reveal that abundant hydroxyl radicals serve as the most active species that enhance photocatalytic degradation of dye on Bi2O3/CA nanofiber membrane. The flexible Bi2O3/CA nanofiber membrane also demonstrates easy recyclability after several runs with no significant decline in performance. This study pins the effectiveness of using eco-friendly cellulose acetate in obtaining inorganic-organic composite to concurrently achieve good photocatalytic performance and recyclability.