Hierarchical porous carbon obtained from animal bone and evaluation in electric double-layer capacitors

Animal bone, an abundant biomass source and high volume food waste, had been converted into a hierarchical porous carbon in a simple two-step sustainable manner to yield a highly textured material. The structures were characterized by nitrogen sorption at 77 K, scanning electron microscopy and X-ray diffraction. The electrochemical measurement in 7 M KOH electrolyte showed that the porous carbon had excellent capacitive performances, which can be attributed to the unique hierarchical porous structure (abundant micropores with the size of 0.5-0.8 and 1-2 nm, mesopores and macropores with the size of 2-10 and 10-100 nm), high surface area (S-BET = 2157 m(2)/g) and high total pore volume (V-t = 2.26 cm(3)/g). Its specific capacitance was 185 F/g at a current density of 0.05 A/g. Of special interest was the fact that the porous carbon still maintained 130 F/g even at a high current density of 100 A/g. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.