Preparação e caracterização do óxido de grafeno funcionalizado com aminas para aplicação em supercapacitadores eletroquímicos

Abstract

A simple and direct method using microwave assisted reactions was presented for functionalization of graphene oxide with aromatic and non-aromatic amines, notably dibenzylamine (DBA), para-phenylenediamine (PPD), diisopropylamine (DPA) and piperidine (PA) as well as its subsequent decoration with nickel and cobalt sulfides.The amine-functionalized graphene oxide (GO-amine) materials were characterized using XRD, FTIR, 13C NMR and XPS, METspectroscopic techniques for image characterization and thermogravimetric analysis (TGA).Composites ofamine-functionalized graphene oxide decorated with nickel and cobalt sulfide particles(GO-amine-sulfide) were also characterized by XRD, FTIR, 13C NMR, MET and TGAtechniques.The characterizations confirmed the functionalizationfor all the amines, reaching relatively high concentrations of superficial nitrogen, up to 8.8%.The investigations of electrochemical behavior for GO-amines showed a significant increase in GO ´selectrochemical propertiesafterfunctionalization, exhibiting long cyclic stability and achieving specific capacitance valuesof 290 Fg-1and 260 Fg-1for GO-PA and G-DPA, respectively, confirming its potential application as alternative support material in supercapacitors.Likewise, the electrochemical characterization of the GO-amine-sulfide composites showed an increase in specific capacitance after the addition of metal sulphides, exhibiting values of 397 Fg-1and 380 Fg-1for GO DPA NiS and GO PA CoS respectively.