Unprecedented 2D GNR-CoB nanocomposite for detection and degradation of malachite green – A computational prediction of degradation pathway and toxicity. (January 2022)

• Record Type: Journal Article
• Authors: Sanjay, B.P.; Sandeep, S.; Santhosh, A.S.; Karthik, C.S.; Varun, D.N.; Kumara Swamy, N.; Mallu, P.; Nithin, K.S.; Rajabathar, Jothi Ramalingam; Muthusamy, karnan
• Is Part Of: Chemosphere. Volume 287:Part 2(2022)
• Publication Date: 2022-01
• Subjects: Malachite green -- GNR-CoB -- Electrochemical sensor -- Photocatalytic degradation -- Density functional theory -- Toxicity; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.132153
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In the present work, we have synthesized a novel 2D GNR-CoB composite and was applied it for electrochemical sensing and photocatalytic degradation of the malachite green (MG). The physicochemical properties of the 2D GNR-CoB were analyzed using X-ray diffraction, Transmission electron microscopy, Energy dispersive X-ray diffraction which depicts the morphological and crystalline nature of the prepared composite. The pencil graphite electrode modified with 2D GNR-CoB composite showed excellent electrochemical response for MG detection with a LOD of 1.92 nM, linear range of 25–350 nM with a high sensitivity of 1.714 μA μM −1 cm −2 . Besides, the 2D GNR-CoB modified PGE exhibited good recovery for the detection of MG in real samples such as green peas and lady's fingers. Furthermore, the 2D GNR-CoB modified electrode showed excellent photocatalytic activity for the degradation of MG. It suggests that under visible light, GNR-CoB material generates superoxide (· O2 − ) and hydroxyl (· OH) radicals for MG degradation. The prepared composite showed an efficiency of 91.28% towards the degradation of MG. Based on the experimental analysis and density functional theory calculations, a photocatalytic degradation mechanism pathway for MG is proposed. A quantitative structure-activity relationship study was used to examine the toxicity of the degradation intermediates. Graphical abstract: Image 1 Highlights: 2D GNR-CoB is employed as electrode matrix on the PGE to construct a MG sensor. Fabricated sensor exhibited high sensitivity & low detection limit. The GNR-CoB exhibited excellent photocatalytic property. The percentage degradation was found to be 91.28%.