Heterogeneous Fenton-like surface properties of oxygenated graphitic carbon nitride

• Published in: Journal of colloid and interface science Vol. 587; pp. 479 - 488
• Main Authors: Oliveira, Wanessa L., Ferreira, Meiriele Antunes, Mourão, Henrique A.J.L., Pires, Manoel J.M., Ferreira, Vinícius, Gorgulho, Honória F., Cipriano, Daniel F., Freitas, Jair C.C., Mastelaro, Valmor R., Nascimento, Otaciro R., Ferreira, Dalva E.C., Ramos Fioravante, Frederico, Pereira, Márcio C., de Mesquita, João P.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2021
• Subjects: carbon nitride; catalysts; catalytic activity; Fenton-like reaction; graphene; Graphitic carbon nitride; hydrogen peroxide; indigo carmine; oxidation; Oxygenated functional groups; Fenton-like reaction; Oxygenated functional groups; Graphitic carbon nitride
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2020.12.031

[Display omitted] The photo-Fenton activity of graphitic carbon nitride (g-C3N4) has been widely studied, nevertheless, its Fenton-like catalytic behavior in the dark has not yet been demonstrated. In the present work, it is shown that oxygenated g-C3N4 obtained at different temperatures (500–600 °C) can degrade indigo carmine with hydrogen peroxide in the dark by a reaction similar to a conventional Fenton’s reaction. Based on an extensive characterization of g-C3N4, we conclude that Fenton-like activity is directly related to the oxygenated functional groups on g-C3N4 structure, mainly by –OH functional groups. Oxygenated functional groups (e.g., hydroquinone-like groups) can reduce the H2O2 and generate oxidizing hydroxyl radicals, just like in the Fenton reaction performed by metals. In addition to new information on g-C3N4 surface reactivity revealed by this study, the metal-free oxygenated g-C3N4 catalyst may be an alternative to traditional metal catalysts used in Fenton-like reactions for advanced oxidation.