Unveiling the Photocatalytic Potential of CoFe ₂ O ₄ Nanoparticles in the UV-Induced Degradation of 4-Aminophenol

Introduction: Industrial wastewater often contains toxic and persistent pollutants, such as phenols and nitrogen-containing derivatives like 4-aminophenol (4-AP), which are resistant to conventional treatments. Advanced oxidation processes, particularly semiconductor-based photocatalysis, offer sustainable alternatives. Objective: This study aimed to investigate the photocatalytic efficiency of CoFe2O4 nanoparticles for UV-induced degradation of 4-aminophenol (4-AP), a toxic phenolic pollutant in industrial wastewater, by correlating their structural, morphological, and optical properties with degradation performance. Methods: CoFe2O4 nanoparticles were prepared using a sol-gel method and subsequently calcined at 600°C. The structural and morphological features were analysed using XRD, FTIR, FE-SEM, and Raman spectroscopy. For photocatalytic studies, a 10-ppm solution of 4-aminophenol was exposed to UV-LED light (375 nm, 9W) under continuous stirring. At 15-minute intervals, aliquots were withdrawn, filtered, and their absorbance was measured using UV-Vis spectroscopy to assess the degradation efficiency. Results and Discussion: CoFe2O4 nanoparticles with high crystallinity, a suitable bandgap (2.65 eV), and favorable surface features exhibited strong photocatalytic activity, achieving 77% degradation of 4-AP (10 ppm) within 120 minutes using only 5 mg of catalyst under UV-LED light. The process followed pseudo-first-order kinetics (k = 0.0125 min-¹), with efficiency strongly dependent on catalyst dosage and irradiation time. Conclusion: CoFe2O4 nanoparticles demonstrated excellent potential as efficient, UV-responsive photocatalysts for degrading toxic organic pollutants like 4-aminophenol. Their tunable optical properties, high reusability, and effective performance under low-power UV-LED light make them promising candidates for sustainable and scalable wastewater treatment applications.