A Novel In Situ Biosynthesized Bacterial Cellulose/MoS2/TiO2 Composite Film for Efficient Removal of Dyes and Pathogenic Bacteria from Industrial Wastewater under Sunlight Illumination

Developing multifunctional water purification materials is of great significance for the elimination of organic pollutants and bacterial pathogens in industrial wastewater. Herein, we report a novel green material, bacterial cellulose/molybdenum disulfide/titanium oxide (BC/MoS2/TiO2) composite film, through one-step in situ biosynthesis, and its application in industrial wastewater treatment. The systematic physicochemical characterization of BC/MoS2/TiO2 demonstrated that MoS2 and TiO2 were effectively incorporated into the BC porous network matrix. Meanwhile, BC/MoS2/TiO2 was absorbed in the UV, visible, and NIR regions with a bandgap of 1.93 eV, indicating that it can serve as a sunlight-excited photocatalyst. Further photocatalytic studies revealed that the synergistic effect of MoS2 and TiO2 enabled BC/MoS2/TiO2 to generate large amounts of •OH and O2•–, and the potential photocatalytic mechanism was investigated. Additionally, BC/MoS2/TiO2 exhibited higher photodegradation efficiencies against methylene blue (k = 0.01963 min–1) and rhodamine B (k = 0.01844 min–1), as well as better photodynamic and photothermal antibacterial performances against Staphylococcus aureus (99.9929%) and Escherichia coli (99.8935%) than BC/MoS2 or BC/TiO2 alone. BC/MoS2/TiO2 showed great reusability and maintained its effectiveness after four cycles. Overall, these results revealed that the biosynthesized BC/MoS2/TiO2 achieved favorable photodegradation of organic dye pollutants via a type I photodynamic pathway under sunlight illumination and synergistic photothermal and photodynamic antimicrobial activity, thus suggesting that this mild, green, and sustainable composite is a promising material for efficient antibacterial and degradation of industrial wastewater constituents.