Synthesis and Chacterization of Polyaniline and Poly(ortho-methoxianiline) Graphene Oxide Nanocomposites for Supercapacitors Application
The aim of this work is to study the synthesis and characterization of polyaniline (PANI) and poly(ortho-methoxianiline) (POMA) graphene oxide (GO)-containing nanocomposites. These materials can be applied in different areas, such as supercapacitors. The PANI and POMA synthesis will be carried out by using chemical synthesis in aqueous acid medium with different monomer:oxidizing agent molar ratios. The ammonium persulfate will be used as a oxidizing agent. The 4:1, 2:1 and 1:1 monomer:oxidizing agent molar ratio will be used in the PANI and POMA synthesis in order to investigate the polymer morphology and the yield of the polymerization reaction. The graphene oxide synthesis will be carried out by using the modified Hummers method. The graphite sample will be oxidized in the presence of mixture of sulphuric acid and potassium permanganate followed by purification steps. The graphite oxide will be obtained by using an ultrasound-assisted exfoliation process in aqueous medium. The graphene oxide containing nanocomposites will be synthesized by using an in situ polymerization process. The material characterization will be carried out by using spectroscopic techniques (FTIR, UV-Vis), morphological characterization (scanning electron microscopy, SEM), X-ray diffraction (XRD) and electrochemical characterization (cyclic voltammetry, charge/discharge tests, electrochemical impedance spectroscopy). The preliminary results obtained in the synthesis of the graphene oxide showed that the graphene oxide was obtained as it can be seen from the SEM and XRD results. The effect of the monomer:oxidizing agent molar ratio in the PANI and POMA synthesis showed that the yield was increased as the amount of oxidizing agent was increased to 1:1. These results will allow the control of the percentage by weight (mass fraction) composition of the nanocomposites synthesized. Unfortunately, the access to the UFABC laboratory facilities is not allowed during the COVID-19 pandemic. Thus, the PANI and POMA morphological and spectroscopic characterization as well as the GO and graphite oxide spectroscopic characterization were not possible to be done. Therefore, the next steps will be carried out according to the directions and instructions that must be approved by UFABC regarding the return to the campus and the access to the laboratory facilities.