EFFECT OF GRAPHENE OXIDE LOADING ON THE STRUCTURAL AND PHOTOCATALYTIC PROPERTIES OF CuO/GO COMPOSITES FOR BASIC FUCHSIN DEGRADATION

Abstract

A series of CuO/GO composites with GO loadings of 0.2, 0.4, and 0.6 g were prepared by a wet chemical precipitation route and tested for their ability to photocatalytically degrade Basic Fuchsin (BF) dye under visible light irradiation. XRD, FTIR, SEM, and UV-Vis spectroscopy were employed to probe the structure, morphology, and optical behaviour of the resulting materials. XRD confirmed the monoclinic phase of CuO in all samples, with crystallite size decreasing progressively from 16.2 nm (pristine CuO) to 9.7 nm (CuO/GO-0.6) with increasing GO content, suggesting that GO sheets inhibit CuO crystal growth. SEM revealed improved particle dispersion in CuO/GO-0.4, providing more accessible active sites for photocatalysis. Of all the composites tested, CuO/GO-0.4 gave the best performance, degrading 97% of the BF dye with a rate constant of 0.0480 min⁻¹, roughly 40-fold higher than that recorded for photolysis alone. Radical scavenging experiments established that hydroxyl radicals (^●OH) and superoxide radicals (O₂^●⁻) are the dominant reactive species, with holes ( ) playing a negligible role. The catalyst also demonstrated good stability, retaining over 88% degradation efficiency after four reuse cycles.