Resumo:
Using alternative routes to obtain functional graphene derivatives is imperative, as traditional methods such as Brodie, Staudenmaier, and Hummers employ highly potent oxidizing agents. In this study, a nanocomposite comprising graphene oxide (GO), metallic copper (Cu0), and copper (I) oxide (Cu2O) was developed through electrochemical synthesis. Initially, GO was prepared via electrochemical exfoliation of graphite (Gr) in a 0.5 M sulfuric acid (H2SO4) electrolyte solution, with the voltage ranging from +3 V to +7 V over 20 minutes. Subsequently, the GO/Cu-Cu2O nanocomposite was synthesized in three different ratios via electrosynthesis, maintaining a constant current of 50 mA for one hour using the galvanostatic method. During electrosynthesis, cupric ions (Cu2+) were reduced to copper and copper (I) oxide (Cu-Cu2O) nanoparticles (NPs), stabilized in an aqueous dispersion of GO. The NPs, GO, and nanocomposites (NCs) underwent characterization using various techniques, including UV-vis spectroscopy, FTIR, Raman spectroscopy, TGA, XRD, and SEM. The results confirmed a 72% yield of GO with a good oxidation level, although TGA revealed impurities in the final material. The successful synthesis of NCs was achieved, and XRD analysis indicated that a low GO content hinders the oxidation of Cu0.