TiO2-modified g-C3N4 nanocomposite for photocatalytic degradation of reactive red 120 in aqueous solution

Wastewater from these industries contains organic residues such as dyes, causing serious water pollution. This study focuses in the synthesis of TiO 2 /g-C 3 N 4 nanostructured hybrid materials and the evaluation of their photocatalytic efficiency in degrading reactive red 120 (RR 120) dye in aqueous environment. The material was successfully fabricated via a pyrolysis method, creating a robust heterojunction structure between anatase TiO 2 and g-C 3 N 4 . Advanced characterization techniques such as Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray Diffraction (XRD), and Ultraviolet-Visible (UV-Vis), revealed that the composite possesses a porous morphology, high crystallinity, and a significantly reduced bandgap of 2.9 eV, enhancing light adsorption capabilities compared to pristine TiO 2 . The effects of key operating parameters: pH, catalyst dosage, and initial concentration were systematically investigated. Experimental results indicated that TiO 2 /g-C 3 N 4 achieved impressive degradation efficiency 99% after 160 minutes of irradiation under optimal conditions like pH of 3, catalyst dosage of 0.8 g/L, and RR 120 concentration of 20 mg/L. The substantial enhancement in photocatalytic activity is attributed to the synergistic mechanism at the heterojunction interface, which facilitates efficient spatial separation of photogenerated electron hole pairs, suppresses recombination, and promotes the generation of reactive oxygen species (OH • , O 2 •- ) for pollutant mineralization. This study confirms that TiO 2 /g-C 3 N 4 is a highly effective and promising photocatalyst with practical applications in textile wastewater treatment. • A novel heterogeneous photocatalyst has been proposed for the removal of RR 120. • TiO 2 /g-C 3 N 4 system exhibits superior decolorization efficiency. • Mechanism removal RR 120 by TiO 2 /g-C 3 N 4 system is due to species of OH • , O 2 •- . • Removal was 99% at pH 3, RR 120 concentration of 20 mg/L, TiO 2 /g-C 3 N 4 of 0.8 g/L.