Research And Optimization Of Performance Of The Graphene Supercapacitor

The high conductivity and high specific surface area of graphene make it very suitable for supercapacitor electrodes.Now how to achieve high-quality graphene production is a hot research. In this paper, based on the improved Hummers preparation of graphite oxide, we obtained graphene through the tube furnace reduction, and then characterize the graphene by XRD, SEM, TEM and BET test, the graphene specific surface area is853m2/g.Nickel foam and aluminum foil are two commonly used collection of fluid materials. Aluminum foil have higher conductivity than the nickel foam,but aluminum foil’s surface is too smooth to adhered active material.In this paper, we etching the aluminum foil surface by electrochemical to improve the performance of the supercapacitor. The concrete research content is as follows:1. Using1.0mol/L and1.5mol/L Na2SO4solution as the electrolyte and compared electrochemical performance of the2kinds of supercapacitor. The results prove that1.0mol/L Na2SO4solution is more suitable for supercapacitor electrolyte.2. Using nickel foam and aluminum foil as collector system for supercapacitor and compared the electrochemical properties of the two, it is concluded that nickel foam’s performance is better than aluminum foil.We can consider to etching aluminum foil to improve the electrochemical properties of supercapacitor whose colletor is aluminum foil.3. Based on the study of the electrochemical etching aluminum foil, we analyze the influence of solution concentration ratio, time and current density on the capacitance and find relatively optimized etching process:HCl, H2SO4concentration ratio is3:1, etching current density is70mA/cm2, etching time is140s.In this condition,the aluminum foil has the best capacitor performance.