Hydrothermal Synthesis of TiO[subscript2]/ZnO/RGO Nano-composite Photocatalysts: Enhancing Photocatalytic Activities for Contaminant Degradation

Abstract

This study focuses on the synthesis and application of a TiO[subscript2]/ZnO/RGO (TZR) nanocomposite integrated with micro-nano bubble (MNB) technology for the effective degradation of indigo carmine (IC), reactive black 5 (RB5) dyes, and carbaryl pesticides. The combination of advanced nanomaterials with MNB aims to enhance photocatalytic efficiency, addressing limitations in conventional wastewater treatment methods. The TZR nanocomposite was synthesized using a simple and cost-effective hydrothermal method, ensuring a well-dispersed structure with improved photocatalytic properties. Comprehensive structural, morphological, and optical characterizations, including XRD, XPS, FTIR, SEM-EDS, HR-TEM, BET, PL, and UV-DRS analyses, confirmed the successful formation of the composite with a heterogeneous distribution of its components. The photocatalytic performance of TZR was evaluated under visible light irradiation, and its efficiency was compared to other composite variations, including TZ, TR, and ZR. Additionally, the integration of MNB technology was employed to enhance the dispersion of the nanocomposite and improve oxygen transfer, facilitating more effective interaction between the photocatalyst and pollutants. The results demonstrated that TZR achieved degradation efficiencies of 98.30%, 97.83%, and 97.17% for IC, RB5, and carbaryl, respectively, within 120 minutes. The synergistic effect of TiO[subscript2], ZnO, and RGO contributed to enhanced electron-hole separation, increased surface area, and broader light absorption. Incorporating MNB technology significantly boosted degradation efficiency, achieving 99.08%, 98.73%, and 98.98% for IC, RB5, and carbaryl, respectively, in the same duration. These findings highlight the potential of combining advanced nanocomposite photocatalysts with MNB technology for sustainable and highly efficient wastewater treatment applications.