Estimating hydroxyl/epoxy ratio in graphene oxide through adsorption experiment and semiempirical GFN2-xTB quantum method.

Autor: Souza LCA; Department of Chemistry, Institute of Natural Sciences, University of Lavras, Lavras, 37200900, Brazil., Abreu RVA; Department of Chemistry, Institute of Natural Sciences, University of Lavras, Lavras, 37200900, Brazil., Guerreiro MC; Department of Chemistry, Institute of Natural Sciences, University of Lavras, Lavras, 37200900, Brazil., Oliveira JE; Department of Engineering, School of Engineering, University of Lavras, Lavras, 37200900, Brazil., Anconi CPA; Department of Chemistry, Institute of Natural Sciences, University of Lavras, Lavras, 37200900, Brazil. cleberanconi@ufla.br.
Jazyk: angličtina
Zdroj: Journal of molecular modeling [J Mol Model] 2023 Jan 18; Vol. 29 (2), pp. 42. Date of Electronic Publication: 2023 Jan 18.
DOI: 10.1007/s00894-023-05444-4
Abstrakt: Context: The reactivity of graphene oxide (GO) with amines is related to the ring-opening of the epoxy groups in its basal surface, as addressed experimentally. Therefore, discussing the hydroxyl/epoxy ratio for GO is relevant to improve the characterization of such material. As the adsorption of Methylene Blue into GO is related to a graphene derivative's oxidation degree (OD), we combined adsorption experimental information and theoretical data to estimate the hydroxyl/epoxy ratio. The theoretical data were compared to the experimental adsorption of Methylene Blue and Indigo Carmine into GO synthesized in our department. Our results show GO systems with hydroxyl/epoxy ratios equal to 0.7, 0.8, and 0.9 are the most representative in which the most coherent model corresponds to OH/EP=0.8 for our GO previously synthesized.
Methods: The GO-MODEL software was developed in the present work to obtain cartesian coordinates of GO systems. We investigated 204 systems comprising models with 486 carbon atoms with the GFN2-xTB semiempirical quantum method. The supramolecular arrangements were constructed with the recently developed UD-APARM program.
(© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
Databáze: MEDLINE
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