Fabrication of TA-Fe3O4/g-C3N4/bacterial cellulose composite membranes as catalytic materials for textile dye degradation

Textile wastewater containing synthetic dyes presents major environmental challenges due to its persistence, toxicity, and resistance to conventional treatment methods. In this study, a composite membrane based on bacterial cellulose (BC) was developed by incorporating graphitic carbon nitride (g-C 3 N 4 ) and Fe 3 O 4 nanoparticles, with tannic acid (TA) employed as a green crosslinking and surface-modifying agent to enhance interfacial compatibility and stability. The resulting TA–Fe 3 O 4 /g-C 3 N 4 /BC composite membrane was fabricated via in situ deposition and assembly, producing a robust, porous, and flexible structure. It was developed for the catalytic degradation of model textile dyes, methylene blue (MB) and methyl orange (MO). Characterization confirmed the successful incorporation and uniform dispersion of active components, along with improved structural and thermal properties. The composite membrane with the presence of Fe 3 O 4 exhibited enhanced catalytic activity, achieving efficient degradation of both cationic (MB) and anionic (MO) dyes. The composite membrane containing Fe 3 O 4 exhibited enhanced catalytic activity, achieving efficient removal of both MB and MO. This work highlights the potential of the developed composite membrane as a catalytic platform for the treatment of dye-contaminated textile wastewater.