Enhanced Photocatalytic Activity of Graphene Oxide–ZrO2 Nanocomposites for Environmental Remediation

Photocatalysis has emerged as a green and sustainable approach for the degradation of persistent organic pollutants. In this study, graphene oxide (GO) and zirconium oxide (ZrO₂) nanomaterials were synthesized and employed as photocatalysts to enhance the degradation efficiency of xylidineponceau (XP) dye, a model pollutant. The photocatalytic performance of GO-ZrO₂ nanocomposites was evaluated under various experimental conditions, including catalyst dosage, pH, dye concentration, and exposure time. Optimal degradation was achieved at a catalyst dose of 0.2 mg/L, an initial dye concentration of 20 mg/L, and a neutral pH of 7.5, resulting in approximately 95% colour removal. Structural and morphological features were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM), while Energy Dispersive Spectroscopy (EDS) confirmed the elemental composition. UV-Vis diffuse reflectance spectroscopy (UV-DRS) was used to determine the optical properties and band gap of the nanocomposite. Kinetic analysis revealed that the degradation followed pseudo-first-order kinetics. The results demonstrate the promising potential of GO-ZrO₂ nanocomposites as efficient photocatalysts for wastewater treatment applications.