<![CDATA[Textile wastewater containing synthetic dyes poses persistent environmental challenges due to its toxicity, chemical stability, and resistance to conventional treatment processes. This study evaluates the photocatalytic degradation performance of zinc oxide (ZnO) toward Congo Red (azo dye) and Rhodamine B (xanthene dye) under ultraviolet light-emitting diode (UV LED) irradiation. ZnO was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM), confirming the formation of crystalline, phase-pure hexagonal wurtzite ZnO with nanoscale morphology and mesoporous features. The crystallite size estimated using the Scherrer equation ranged from 25.9 to 33.2 nm. Photocatalytic experiments were conducted at different initial dye concentrations (5–20 mg/L) with irradiation times up to 30 min. Under the investigated conditions, Rhodamine B achieved up to 97.2% removal, while Congo Red reached 89.3% removal. Kinetic analysis indicated apparent pseudo-first-order behavior with rate constants of 0.091 and 0.072 min−1 for Rhodamine B and Congo Red, respectively. Control experiments confirmed the essential role of UV LED irradiation in promoting photocatalytic activity. These findings demonstrate that ZnO activated by UV LED irradiation exhibits promising potential for efficient, sustainable, and environmentally friendly dye degradation in wastewater treatment under optimized experimental conditions with significant practical applicability.]]>
