Effect of initial concentration on the photocatalytic degradation of remazol brilliant blue dye using nickel catalyst

In this study, EGNiO catalyst was successfully synthesized using electrochemical method. An amount of 1.25 g/L of catalyst dosage was found to provide the optimum dosage for 10 mg/L remazol brilliant blue (RBB) dye resulting in a 90.0% of degradation within 1.5 h of contact time at pH 3 (acidic medium) under light irradiation. It is suggested that at lower concentration more active sites and hydroxyl radicals were available to attacks and destroyed the RBB molecule. However, at higher concentration, lower degradation was achieved due to the formation of several layers of adsorbed dye molecule on the catalyst surface, thus inhibits the photoreaction since there was no direct contact of light in order to generate the formation of hydroxyl radicals. The good photoactivity and photoresponse in visible light regions give advantage to the system to be used practically in the wastewater treatment industries. (C) 2019 Elsevier Ltd. All rights reserved.