GREEN SYNTHESIS AND CHARACTERISATION OF COPPER OXIDE NANOPARTICLES - REDUCED GRAPHENE OXIDE NANO COMPOSITES FOR FACILE ELECTROCHEMICAL OXIDATION OF PONCEAU 4R AND ALIZARIN RED DYES IN AQUEOUS MEDIUM

Copper oxide nanoparticles are prepared to adopt the green synthesis route by using Aloe vera plant extract instead of synthetic and polymeric stabilizing agents in mild alkaline aqueous conditions. The synthesized CuO nanoparticles (CuO NPs) are characterized by Powder XRD and HR-TEM measurements. Using the as-synthesized CuO NPs and reduced graphene oxide (rGO), nanocomposites comprising CuO NPs- rGO are prepared by hydrothermal and ultrasonic methods. Nanocomposites are characterized using Powder XRD, HR-TEM, and FE-SEM data. The fabricated CuO NPs-rGO nanocomposites are coated onto glassy carbon electrode (GCE) for facile detection and electro-oxidation of water-polluting dyes such as the Ponceau 4R (P4R) and Alizarin Red (AR) using cyclic voltammetry. Electrooxidation of the dyes occurred at appreciably lower oxidation potentials like 0.45 V and 0.6 V for P4R and AR respectively along with the decoloration of the dyes. The absorbance of the analyte dye solutions is measured at intervals of time of the progress of electro oxidations. The overall first- order rate coefficient values for dye degradations are found out from absorbance time variance data. The results indicate that CuO NPs-rGO nanocomposites decorated GCE acted as an efficient electrode surface for sensing and degradation applications for the chosen dye solutions. P4R azo dye degradation response was found to be better than AR anthraquinone dyes.