Bacterial cellulose based TiO2-CdS nanocomposite gel with enhanced photocatalytic activity for adsorptive degradation of cationic dye

Abstract

Dye released by industrial is one of the main known pollutants in wastewater, which is harmfully affected to the human health. Adsorptive method by absorbents and photocatalytic degradation technique are advanced technologies to remove dyes from wastewater. However, the single technique mentioned above has imperfections limiting its application. Herein, in order to integrate the two techniques and take both advantages, bacterial cellulose (BC) based titanium dioxide (TiO₂)‑cadmium sulfide (CdS) nanocomposite gel was prepared by microwave-assisted solvothermal synthesis. The BC@TiO₂-CdS nanocomposite gel was characterized by SEM, EDS, XRD, XPS, Raman spectral and TG, its photocatalytic mechanism was proved by PL. The results showed the TiO₂-CdS nanophotocatalyst exhibited binary hierarchical structure and followed the Z-scheme type photocatalytic system. The Z-scheme heterojunction is advantageous for photo-generated charge separation and migration. The photocatalytic performance of BC@TiO₂-CdS nanocomposite gel was evaluated by MB degradation under visible light irradiation. Due to synergistic effect of BC matrix and TiO₂-CdS, the as-prepared BC@TiO₂-CdS nanocomposite gel possesses enhanced photocatalytic activity with 94.47 % removal of methylene blue (MB) after 180 min visible light irradiation. Therefore, this work provides a facile route to fabricate bio-mass based efficient nanophotocatalytic material for pretreating the water pollution.

Keywords: Bacterial cellulose; Nanocomposite; Photocatalyst.