Waste bones derived nitrogen–doped carbon with high micropore ratio towards supercapacitor applications.

Waste bones derived nitrogen–containing carbon with the higher S Micro /S Total value achieves a specific capacitance of 302F g−1 at 0.5 A g−1. Fabrication of high–performance electrodes from waste biomass has attracted increasing attention among the energy storage and conversion field. In this work, we have synthesized nitrogen–doped activated carbon by a simultaneous pyrolysis/activation method from waste bones. It is found that the specific surface area and pore structure of as–synthesized carbon depends on the carbonization temperature (500–800 °C), and the highest specific surface area is 1522 m2 g−1. The electrochemical properties of Pork bone, Blackfish bone, Eel bone based activated carbon (PBAC, BFAC, EBAC) mainly depend on their micro–/mesoporosity. Three samples PBAC–600, BFAC–600 and EBAC–600, which have higher ratio of micropore surface area and nitrogen content, exhibit enhanced specific capacitance of 263, 302 and 264F g−1 in 6 M KOH electrolyte. Furthermore, the assembled symmetric supercapacitors of PBAC–600 can deliver energy density as high as 7.0 and 26.2 Wh Kg−1 in the aqueous and ionic liquid electrolyte, respectively. Such excellent performance can be attributed to the microporous structure, reasonable pore size distribution and nitrogen self–doping of the activated carbon. This research indicates that waste bones have great potential for mass fabrication of the activated carbon electrodes for energy storage applications. [ABSTRACT FROM AUTHOR]