Effective conversion of Cassia fistula dry fruits biomass into porous activated carbon for supercapacitors

The present research article reports the simple, economic and eco-friendly conversion of the waste biomass derived from Cassia fistula dry fruits into a porous Activated carbon (CF AC) by KOH chemical activation method and utilization of CF AC samples as electrode materials in supercapacitor application. The CF AC samples were pyrolyzed at different temperatures to determine the effect of activation temperature on the capacitive performance of the electrode materials. The as-prepared CF AC samples were characterized using various spectral and analytical techniques, such as FTIR, Raman, XRD, BET, XPS FESEM, EDAX and TEM analysis systematically. Initially, the supercapacitor measurements were performed in three electrode system and the results revealed that the CF-800 electrode demonstrated the highest specific capacitance (583 F/g at 1 A/g current density) and capacitance retention value of 91% even after 5000 GCD cycles at 1 A/g current density. Thus CF-800 sample was used to fabricate CF-800||CF-800 symmetric device. The as-constructed device delivered an energy density of 11.11 Wh kg(1) corresponding to the energy density of 333.3 W kg( 1). This observation proved that the as prepared Cassia fistula dry fruits derived activated carbons (CF AC) make a great impact in the production of low-cost and efficient electrodes for supercapacitors.