Sustainable Development of Graphene Oxide from Pine Leaves for Electrochemical Energy Storage and Corrosion Protection

Abstract

Present investigation demonstrates application of pine leaves as green friendly source for production of biochar (BC) that could to transformed into graphene oxide (GO) for sustained electrochemical energy storage (EES) and corrosion protection in KOH (2.0 M). For this purpose, BC was prepared through pyrolysis of pine leaves (moisture content 78.09 %) at 750 o C over 3 h in nitrogen environment. GO was synthesized through modification in Hammer’s method. Formation of BC and GO was ascertained through Fourier transform infrared, Raman and X-ray diffraction spectra. Working electrodes (WE) were fabricated from BC (WE BC ) and GO (WE GO ) in presence of hydroxy methyl propyl cellulose as binder and their morphologies were compared through scanning electron microscopy. WE were electrochemically analyzed through cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and potentiodynamic polarization in KOH (2.0 M). CV @ 0.005 V/s in potential window of -0.71 V to -0.21 V reveals 390.4 F/g of Cs of WE GO that was 24.49 % improved over WE BC . EIS in frequency response (KHz) ranging 1.0 × 10 -5 Hz to 100 at ± 0.005 V reveals stability of WE over 24 h. Potentiodynamic polarization in the potential ranging -1.5 to 1.0 @ 0.005 V/s reveals corrosion rate (mm/year) of WE GO @ 4.69 × 10 -4 that was much reduced over WE BC (2.27 × 10 -3 ) under identical conditions.