Strategy for Preparing Porous Graphitic Carbon for Supercapacitor: Balance on Porous Structure and Graphitization Degree

Abstract

An ideal carbon material for supercapacitors should simultaneously satisfy large specific surface area and good conductivity to ensure enough space for charge storage and rapid electron transport, respectively. So, the design of facile synthesis for porous graphitic carbon (PGC) with large surface area and high conductivity is extremely important in energy storage. Disposable chopstick derived from renewable biomass is usually discarded as a waste. Herein, we provided a novel strategy to convert disposable chopstick into high-value-added PGC by one-step carbonization and using K2C2O4 and Fe(NO3)3 as activating agent and graphitic catalyst, respectively. The results of SEM, XRD, Raman and N2 adsorption–desorption indicated that the obtained PGC has developed porous structure and high graphitization degree, which can be easily controlled by tuning the amount of K2C2O4 and the carbonization temperature. When tested as an electrode, the optimal sample, namely, PGC-4-850, showed excellent specific capacitive behavior of 231.1 F g−1 at 0.2 A g−1 and remarkable cycling stability with only 3.4% degradation after 10000 cycles. Considering that the process is simple and the waste chopstick can be effectively utilized and replaced by other biomass, it is a promising route to produce PGC for energy storage.