Superior Capacitive Performance of Active Carbons Derived from Loofah Sponge

In this paper, loofah sponge-based activated carbon (LAC) is prepared via loofah sponge as precursors and KOH as activator. N₂ adsorption, X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the surface morphology and the structure of loofah sponge-based activated carbon. Cyclic voltammetry (CV), galvanostatic charge/discharge cycle and electrochemical impedance spectroscopy (EIS) were utilized to test electrochemical properties of loofah spongebased activated carbon. The results showed that loofah sponge-based activated carbon (LAC-700) prepared at 700 °C has the highest specific surface area (936 m²·g^-1). The material delivers specific capacitance of 152.89 F·g^-1 at the current density of 0.1 A·g^-1, and specific capacitance of 116.69 F·g^-1 at the current density of 5 A·g^-1 in 30 wt% KOH aqueous electrolyte.