Effective degradation of aqueous bisphenol-A using novel Ag₂C₂O₄/Ag@GNS photocatalyst under visible light

Photocatalytic oxidation of toxic pollutants is a proficient technique to solve the problems associated with the treatment of bisphenol-A which is classified as 1B reprotoxic substance. In this paper, Ag₂C₂O₄/Ag@GNS nanocomposite whereas Ag and graphene nanosheets (GNS) used as the charge carriers, which is combined through peroxymonosulfate (PMS) for the removal of bisphenol-A (BiP-A) for the first time. The XRD, UV-DRS, SEM, and TEM studies were performed to confirm the phase structure and the purity. Ag₂C₂O₄/Ag@GNS nanocomposite exhibited superior photocatalytic performance and removal rate when compared with pure Ag₂C₂O₄ and pure GNS. In Ag₂C₂O₄/Ag@GNS photocatalyst, the deposited Ag on the surface of Ag₂C₂O₄ rods effectively formed a metal and semiconductor heterostructure, thus photogenerated charge carriers were separated easily by the surface plasmon resonance effect (SPR) effect of noble Ag. Hence charge carriers lifetime has been extended to a great extent for the better photocatalytic performance. The experimental results confirmed that the ̊ O₂⁻, ̊ OH, ̊ SO₄⁻ radicals were played major role in the photolysis process. Furthermore, the effect of the photocatalyst & PMS concentration, pH and co-existing ions towards the BiP-A degradation were studied in detail. According to the mass spectroscopy studies BiP-A pollutant was effectively deteriorated into smaller molecules and CO₂, H₂O. Furthermore, we have proposed the possible degradation pathway and photocatalytic mechanism for better understanding.