Preparation and application of capacitive carbon from bamboo shells by one step molten carbonates carbonization

Abstract

Molten salt is a superior medium for the carbonization and activation of biomasses due to its unique properties such as oxygen-free, catalysis activity, dissolution capability of impurities and heat-storage capacity. Herein, micro-sheet like porous carbon with high specific capacitance was prepared by molten carbonate salt carbonization (MSC) of bamboo shell, a kind of abundant waste biomass. The obtained product was characterized by SEM, XRD, Raman and BET measurements and was tested as electrode material of electrochemical supercapacitor. The obtained carbon has outstanding performances with a specific gravimetric capacitance of 204 F g−1 and an areal specific capacitance of 1.53 F cm−2 at a current density of 1 A g−1 and excellent rate capability as well as good cyclability. Over 96% of the initial capacitance maintained after 5000 cycles. The excellent capacitive property may be ascribed to the large specific surface area, unique surface and pore structure, high electrical conductivity and rapid charge transfer kinetics of the MSC-carbon. The results implied that the strategy of molten carbonates carbonization could be a simple and effective route for converting waste biomasses to value-added carbon material for energy storage application.