Synergistic effect of TiO2-rGO nanocomposites with Fenton’s reagent for the enhanced photocatalytic degradation of nitrophenols in solar light

• Published in: Applied physics. A, Materials science & processing Vol. 128; no. 5
• Main Authors: Anusha, B., Anbuchezhiyan, M., Sribalan, Rajendran, Srinivasan alias Arunsankar, N.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2022; Springer Nature B.V
• Subjects: Applied physics; Catalysts; Catalytic activity; Characterization and Evaluation of Materials; Charge materials; Chemical composition; Condensed Matter Physics; Graphene; Machines; Manufacturing; Materials science; Nanocomposites; Nanotechnology; Optical and Electronic Materials; Photocatalysis; Photodegradation; Physics; Physics and Astronomy; Processes; Raman spectroscopy; Reagents; Reducing agents; Sunlight; Surface charge; Surfaces and Interfaces; Synergistic effect; Thin Films; Titanium dioxide; Ultraviolet radiation; X ray photoelectron spectroscopy; Zeta potential; Solar light; Fenton’s reagent; Photocatalysis; rGO nanocomposites; Nitrophenols; TiO; Hydroxyl radical
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-022-05554-5

In the present study, Graphene Oxide (GO) was prepared by the modified Hummer’s method. Further, different wt% of reduced Graphene Oxide (rGO) decorated TiO 2 (TiO 2 -rGO) nanocomposites were synthesized using non-toxic sodium L-ascorbate as a reducing agent. The structure, morphology, optical and chemical composition of the composites were investigated with analytical techniques such as XRD, FESEM, HRTEM, UV –Vis DRS, FTIR, XPS and Raman spectroscopy. The zeta potential study reveals that the surface charge of the materials is negative and the value increases with the increase in the rGO content which proves residual acid groups on rGO and by the decoration of rGO surface with TiO 2 . The photocatalytic activity of the composites was tested for the degradation of nitrophenols [Mononitrophenol (MNP), Dinitrophenol (DNP) and Picric Acid (PA)] in the presence of the Fenton’s reagent with UV light (wavelengths 254 and 390 nm), visible light and sunlight at different pHs (3,7 and 10). In the presence of Fenton’s reagent, the catalyst TiO 2 -rGO 1% exhibited 100% degradation of nitrophenols in UV light of wavelength 254 nm within 15 min whereas with sunlight the catalysts, TiO 2 -rGO 5% and TiO 2 -rGO 10% exhibited 100% degradation of nitrophenols within 15 min and 18 min, respectively, at pH 3. Thus, the combined catalysts could have much impact on the photocatalytic degradation of water-borne organisms in the future. Graphical abstract