Nitrogen-doped Porous Carbon Derived from Rapeseed residues for High-performance Supercapacitors

摘要

In this paper, nitrogen-doped activated carbons obtained from rapeseed residues (N-RCs) assupercapacitor electrodes are successfully synthesized by a simple chemical activation method. Thefield emission scanning microscope, transmission electron microscopy, and N2 adsorption-desorptiontests demonstrate that N-RCs treated with ZnCl2 can produce a large number of mesopores.Additionally, the N-RCs have certain amount of nitrogen (nitrogen content in N-RC2 is 6.55% byelement content analysis). As the electrode material, N-RC2 exhibits ideal capacitive behavior in 6 mol-1L KOH aqueous electrolyte in a three-electrode system tests, and the maximum specific capacitance-1 -1 -1 reaches 250 F g at a current density of 0.5 A g . Furthermore, in 0.5 mol L Na2SO4 aqueouselectrolyte, the as-assembled N-RC2//N-RC2 symmetric cell exhibits high energy density of 13.55 Wh-1 -1 kg at a power density of 399.80 W kg operated at the voltage range of 0 to 1.8 V and an excellentcycleability retaining about 92.8% initial capacitance after 5000 cycles.