Preparation and electrochemical properties of sucrose-based porous carbon materials by combustion expansion-chemical activation method

Abstract

Inspired by the classic expansion reaction, "Pharaoh's Snake", this study uses sucrose as a carbon source and NaHCO3 as a foaming agent. Since NaHCO3 is decomposed by heat to release a large amount of CO2 gas, the carbonized sucrose is converted into a loosely expanded "snake-like" carbonization under the action of CO2 gas. Then, using argon as the shielding gas and KOH as the activator, the sucrose-based porous carbon material, BZTC-T, was successfully prepared by high-temperature chemical activation. The sucrose-based porous carbon BZTC-T is amorphous carbon with a specific surface area of 2673 m2 g−1 and a reasonable pore size distribution. Cyclic voltammetry and constant current charge and discharge tests show that sucrose-based porous carbon, BZTC-800, shows excellent electrochemical performance with a specific capacitance up to 289 F g−1 at a current density of 1 A g−1 in a 6 M KOH electrolyte. Sucrose-based porous carbon BZTC-800 has good cycle stability after 10,000 cycles of charge and discharge with a capacitance retention rate as high as 93.7%.