Preparation and electrochemical performance of Psidium guajava leaf-based activated carbon for supercapacitor application
摘要
The low cost of preparation and exceptional electrochemical stability of activated carbon have made it a popular choice for supercapacitor electrode materials. Using the residual biomass from Psidium guajava leaves, activated carbon was synthesized in this study and used as an electrode material for supercapacitors. The surface area of AGL-2 (290 m2 g−1) higher than AGL-1 (164 m2 g−1). With a 3 M KOH electrolyte, activated carbon has the highest specific capacitance at 1 A/g, 342 F/g. It exhibits low solution resistance of 0.5 Ω and 96% capacitance retention up to 10000 cycles at a high current density of 30 A/g in a two-electrode setup. A high-power density of 227 W kg−1 and an energy density of 52 W h kg−1 are also displayed by the activated carbon. Long-term endurance in an aqueous electrolyte was demonstrated by the symmetric device.