Fabrication of Supercapacitor Based on Reduced Graphene Oxide for Energy Storage Applications

Abstract

The demand for high-performance supercapacitors (SCs) and non-conventional energy harvesting systems that possess the requirements of high power density and long lifetime is an essential need for future applications. Despite the usage of carbon material in commercial SCs, reduced graphene oxide (RGO) attracted great concerns due to its unique properties such as superior chemical and thermal stability, high surface area, 2D structure, and high electrochemical performance. In this work, reduced graphene oxide (RGO) was synthesized chemically by the reduction of graphene oxide prepared by improved Hummer method then modified by thermal reduction. After that, a symmetric supercapacitor electrodes were prepared by the coating of RGO paste on graphite substrates to reduce contact resistance and promote electrochemical stability. The CR2032 coin-cell was used as the standard cell package and KOH (6M) as a strong alkaline electrolyte. The electrochemical behavior of the cell was investigated by using Bio-Logic VSP-300 where high specific capacitance of 158 F/g was achieved at 5 mv/s scan rate. Interestingly, retention obtained was about 95% after 1000 cycles coupled with power and energy densities and 2000W/Kg and 14.4Wh/Kg at 1A, respectively. On the other hand, the microstructure and surface morphology of RGO was investigated using scanning electron microscopy (SEM) and X-Ray diffraction.