Reduced graphene oxide based metal oxide nanocomposites for supercapacitor applications

Abstract

Although great efforts have been made on development of high performance Li ion batteries and fuel cells in the past the slow power capability and high maintenance cost have kept them away from many applications Recently supercapacitors have drawn great attention because of their high charge discharge rate long life cycle outstanding power density and no short circuit concern The objective of this thesis is to develop grapheme based metal oxide nanocomposite supercapacitors with improved power density and energy density at low production cost Supercapacitors also known as ultracapacitors or electrochemical capacitors store energy as electrical charge on highly structures Currently one major challenge that keeps supercapacitors from their promising applications is the low energy density Hence the present thesis is intended to fill the research gap focusing on PbO nanoparticles PbO CdO PbO ZnO and metal oxide rGO nanocomposites for improving the properties of supercapacitance performance In the present work lead Oxide PbO nanoparticles and the composite form of PbO with CdO and ZnO were prepared by the wet chemical method The crystal structure optical absorption and functional groups of the prepared materials were studied The electrochemical studies indicate that PbO ZnO nanocomposites possess the highest specific capacitance of 408F g compared with that of PbO nanoparticles and the PbOCdO nanocomposites newline