We report the fabrication of multilayer reduced graphene oxide films using UV oven spraying technique for stacking cell model supercapacitor asymmetry. In report, we used nickel and carbon substrates as asymmetric current collectors. Using UV oven spraying technique, graphene oxide was coated and insitu converted on substrate surfaces forming reduced graphene oxide films that act as active materials in supercapacitor asymmetry. The films consist of 70 layers with delay time between consecutive layer prior to irradiation is 4 minutes to ensure the photoreduction take place on each layer. UV light source using Mercury lamp 125 watt at 30 cm above the substrates. The model structures consist of three cells stacked serial in 1M KCl electrolyte system. Device performance was characterized using charge-discharge technique for constant current at 2, 3, 4, 5, and 10 mA. Performance parameters are the capacitance density, power and energy density. Single cell supercapacitor has energy density in range of 0.072 Wh/kg to 0.256 Wh/kg and power density in range of 123.06 W/kg to 644.14 W/kg. Meanwhile for stacked cell supercapacitor has energy density in range of 0.377 Wh/kg to 0.755 Wh/kg, and power density in range of 169.95 W/kg to 849.79 W/kg. According to Ragone Plot, the results have feature as supercapacitor, even as single cell. Stacked cell has feature better than single cell in all parameter of capacitance density, power and energy density, and electrical working potential.
Land Requirements for Utility-Scale PV: An Empirical Update on Power and Energy Density
