Effect of voltage variation on the performance of carbon electrode supercapacitor cell from saba banana bunch biomass

ABSTRAK

In this study, carbon electrodes for supercapacitors were successfully fabricated using saba banana bunch as a biomass precursor. The electrode preparation process comprised multiple stages, including pre-carbonization, chemical activation with a 0.5 M KOH solution, carbonization at 700°C, followed by physical activation under CO2 gas at 800°C for 90 minutes. Physical characterization of the carbon electrodes revealed a significant density reduction of 38.51% post-pyrolysis. Surface morphology analysis indicated a porous structure predominantly consisting of micropores and mesopores. Energy-dispersive X-ray (EDX) spectroscopy confirmed a high carbon content, with a mass percentage of 65.24%. Electrochemical performance was evaluated via cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) measurements at applied voltages of 0.6, 0.8, and 1.0 V. The carbon electrode sample designated SB-1 exhibited the highest specific capacitance values, reaching 74.47 F/g (CV) and 42.58 F/g (GCD). These results indicate that an operating voltage of 1.0 V yields optimal performance for supercapacitor applications employing banana stem-derived carbon electrodes.