Renewable low cost green functional mesoporous electrodes from Solanum lycopersicum leaves for supercapacitors

In this present investigation, functional (conducting) carbon were synthesized by direct pyrolysis method followed by carbonization process from the dead plant leaves of Solanum lycopersicum (SLL)without any external activation and applied for the energy storage system of supercapacitors. This technique is very simple and applicable to most of the dried forms of biomass. The synthesized functional carbon were characterized by X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy (RAMAN), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), Field Emission Scanning Microscopy (FESEM) and Transmission electron microscope (TEM) techniques. The synthesized functional carbon electrode materials of SLL were also tested by cyclic voltammetry (CV), galvanostatic charge and discharge (CD), Impedance analysis in aqueous electrolyte (1 M H2SO4) and cycle stability test. By using three-electrode systems, the electrode material of SLL-1000 shows best capacitance performance of 345 F/g when compared to other samples of dried SLL -600 and 800. The dried leaves of SLL-1000 based supercapacitor exhibits high 43.13 Wh/kg (energy density) at 61.34 W/kg (power density) in 1 M H2SO4. From the results, it highlights the success of preparing high capacitance electrode materials from functional carbon which are micro or mesoporous synthesized from SLL as a raw material for supercapacitors application.