Desenvolvimento de um capacitor de alta performance com multicamadas de polianilina e óxido de grafeno

Abstract

The search for new technologies in energy storage raise important questions about its efficiency and sustainability. In the matter that the seek for new materials that can present good performance and simultaneously do not cause any harm to the environment, being able to provide energy for a long period of time and also maintain the yield as the time passes. Multilayer polyaniline (PANI) and graphene oxide (GO) were deposited in Indium tin oxide (ITO) that was used as substrate, for capacitor application. The graphene oxide was synthesized by modified Hummers method, which is a chemical method. The synthesized material was demonstrated by ray-X diffraction. With Cyclic Voltametry (CV) and Constant Current Charge Discharge Potential Limit (CCCDPL) was possible to obtain the capacitive properties of the PANI and the polyaniline deposited with graphene oxide (PANI-GO) in 1 mol/L H2SO4 solution. The specific capacitance of PANI-GO has shown bigger than the starting material, which is the PANI according to the electrochemical analysis. The values of specific capacitance of the synthesized materials were 201 F/g and 429 F/g for PANI and PANI-GO respectively. This high electrochemical performance of the composite probably is due to the increase of active sites and pores in the structure of the PANIGO, which it favors the ions diffusion in to the structure, thus enhancing its capacitive properties, also the interaction between the polyaniline itself and the graphene oxide by the fact that they have intermolecular interactions that happen to be attractive ones, which make easier to maintain the contact for both. With these results, it is possible to verify that the graphene oxide has a good potential to be used in capacitors and energy-storage devices as well as in systems that use polyaniline as its base.