Investigation on graphene conducting polymer nanocomposite for electrochemical supercapacitor

Abstract

Increased level of energy usage, depletion of fossil fuel and environmental pollution has created huge interest in renewable energy storage device such as supercapacitor and fuel cell. From the operational perspective, supercapacitor is in between capacitors and batteries. With their cycle life, power density, charging time and safety, supercapacitor is the preferred choice for energy storage application for last two decades. Even though it is a promising candidate, a lot of improvements have been expected in terms of electrode materials electrical conductivity, surface area, pore size, pore volume and stability. In this thesis, graphene oxide, graphene oxide/activated carbon composite, graphene oxide/polyaniline composite and graphene oxide/polypyrrole composite prepared by modified hummer s method, hydrothermal method, in-situ polymerization and sacrificial template polymerization method, respectively were investigated as the electrode material of either electrochemical double layer supercapacitor or pseudocapacitor. The different composites were developed in terms of their composition level. Other than these, all the synthesized samples were microwave treated using household microwave oven for the improvement of porous structure of ordinary samples. When compared to microwave treatment of graphene oxide and graphene oxide/activated carbon composite, microwave treatment of the polymeric materials is a difficult task, due to the nature of polymeric materials such as polyaniline and polypyrrole. In this thesis, it has been optimized that the power as well as duration of microwave treatment. In this way, the structural and electrochemical properties of the synthesized materials are improved. newline