College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072, P. R. China
Abstract:
Recently, preparation of carbon materials using biomass as precursors has received much attention owning to their merits of low cost, abundance, renewability, and environmental benignity. In this study, honeycomb-like porous gelatin was synthesized and subsequently used as the precursor to prepare activated carbon through carbonization followed by activation. The prepared activated carbon had a higher specific surface area (up to 3692 m2·g-1) and supercapacitor performance than that of activated carbon derived from commercial gelatin. In a 6 mol·L-1 KOH solution, the activated carbon prepared from porous gelatin through 600℃ carbonization and 700℃ activation delivered high specific capacitances of 357 and 227 F·g-1 at current densities of 1 and 100 A·g-1, respectively. In addition, after 7500 charge/discharge cycles at a current density of 10 A·g-1, it showed 93.0% retention of the initial capacitance, demonstrating excellent cycling stability. Moreover, a symmetric supercapacitor was assembled, which delivered an energy density of 10.3, 9.7, and 8.2 Wh·kg-1 at power densities of 250, 2500, and 25000 W·kg-1, respectively. Furthermore, a capacity retention as high as 97.6% was achieved after 10000 cycles at 10 A·g-1 using this symmetric supercapacitor. This work has demonstrated that the activated carbon derived from honeycomb-like porous gelatin has great potential for application in high-performance supercapacitors.
