High surface area and oxygen-enriched activated carbon synthesized from animal cellulose and evaluated in electric double-layer capacitors

Abstract

Crab shell, an abundant food waste and high volume organic resource, has been used to synthesize oxygen-enriched activated carbon. The thermal stability, surface area, morphology and surface chemical composition were characterized by thermogravimetric analysis, nitrogen adsorption, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The obtained activated carbon had a high surface area of 3442 m² g⁻¹, large pore volume of 2.327 cm³ g⁻¹ and rich surface oxygen species of 18.50 at%. The cyclic voltammogram, galvanostatic charge–discharge and electrochemical impedance spectroscopy tests were performed to investigate the electrochemical properties of the resultant carbon electrodes. The specific capacitance was 280.6 F g⁻¹ at a current density of 0.2 A g⁻¹ and still remained as high as 233.4 F g⁻¹ even at a high current density of 10 A g⁻¹, indicating the great potential of crab shell-activated carbons in the development of electrode materials for high-performance supercapacitors.