Efficient photocatalytic degradation of Congo red and other dyes by ternary TiO₂/Y₂O₃@g-C₃N₄ nanohybrid

A ternary TiO2/Y2O3@g-C3N4 nanocomposite was fabricated by a simple sonochemical method and its photocatalytic activity for organic pollutants was examined. X-ray diffraction analysis, transmission electron microscopy coupled with elemental chemical composition confirmed the formation of network-like nanostructure composed of Y2O3/TiO2 nanoparticles coupled with g-C3N4 nanosheets. Due to its large surface area, low band gap energy, and the presence of photogenerated holes, electrons, and hydroxyl radicals, the nanohybrid composite exhibited excellent photocatalytic degradation of Congo Red dye in an aqueous solution under optimized operational conditions, i.e., 100% for a short time of 60 min. The photodegradation kinetics was validated by the pseudo-first-order model and the photodegradation mechanism was elucidated. This study provides insights into the degradation of hazardous and toxic organic pollutants under visible light illumination.