Synthesis and characterization of activated carbon from the biomass of Saccharum bengalense for electrochemical supercapacitors

Abstract

Abstract Low cost and very simple activation method (ZnCl2 as activating agent) is used for the synthesis of activated carbon derived from the biomass of Saccharum bengalense (S. bengalense) leaves. The S. bengalense derived activated carbon (SbAC) as the electrode material in Electric Double Layer Capacitors (EDLCs) is reported for the first time. The structural, surface morphological study and vibrational response of the SbAC are characterized by using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Brunauer-Emmett-Teller (BET) surface area. Electrochemical studies indicate that the SbAC delivers the maximum specific capacitance of 102.6 F g−1at scan rate of 2 mV/s in aqueous electrolyte (1 M Li2SO4) for 1.6 V operating voltage. This high value of specific capacitance is credited to its high specific surface area (2090 m2 g−1) and pore volume of 0.281 cm3 g−1. The SbAC exhibits good rate capability with an excellent charging/discharging cycle stability in aqueous electrolyte (1 M Li2SO4) during 120,000 cycles. The results indicate that SbAC shows good electrochemical properties to be used for energy storage applications in future.