Function composition of modified reduced graphite oxide. (September 2020)

• Record Type: Journal Article
• Authors: Kobets, A.A.; Lobiak, E.V.; Krivyakin, G.K.; Kallio, T.; Fedorovskaya, E.O.
• Is Part Of: Materials today chemistry. Volume 17(2020)
• Publication Date: 2020-09
• Subjects: Carboxylation -- Cyclic voltammetry -- Oxygen-containing functional groups -- Graphene material -- X-ray photoelectron spectroscopy; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2020.100311
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: Reduced graphite oxide (RGO) is prospective for application as an active material for supercapacitor electrodes due to the simple synthesis, the high specific surface area and the presence of oxygen-containing functional groups. Functionalization of such materials affects hydrophilicity, surface morphology and contributes to the redox processes when potential is applied. In this article RGO was treatment by mixture of potassium hydroxide and chloroacetic acid; hydrobromic acid and oxalic acid; in various ratio of strong nitric, sulfuric and phosphoric acids. Such functionalization of RGO leads to decrease in particle size, increase the quantity of oxygen-containing groups on the surface of the materials and affects the change of carbon hybridization from sp 2 to sp 3 . Furthermore, all the samples were investigated by cyclic voltammetry (CV) to study the redox processes occurring on the electrode material surface. The peaks on the CV curves were compared with the corresponding redox reversible reactions. Furthermore, the specific capacity of all samples was calculated. Thus, at low carboxylation level of RGO specific capacity is increased due to significant contribution of redox processes while high functionalization leads to decrease in conductivity and, as well in specific capacity. Highlights: Series of graphene materials with increasing functionalization degree was created. Weakly carboxylation leads to an increase of capacity due to redox processes. Strong modification leads to decrease of capacity due to destruction of material. Peaks on graphene material cyclic voltammograms were compared with redox processes.