Porous N-doped carbon material derived from prolific chitosan biomass as a high-performance electrode for energy storage

Abstract

Although a wide variety of biomass, such as human hair, chicken eggshells and ox horns, have been used to prepare carbon electrode materials for energy storage, most of them have very limited production, which restricts their large-scale application. Herein, the very prolific biomass of chitosan is employed as an abundant raw material to successfully prepare one porous N-doped carbon material (PNCM). Structural characterizations demonstrate that this PNCM is hierarchically porous with abundant macro/micropores and 4.19% N-doping. The electrochemical properties of the PNCM as electrode materials for both supercapacitors and lithium ion batteries are also studied. When used in a supercapacitor, the optimized PNCM synthesized at 700 °C can store electrical energy with a specific capacitance of up to 220 F g⁻¹ in 1 mol L⁻¹ H₂SO₄ electrolyte, exhibit excellent cycle stability with only 1.3% capacitance decay over 11 000 cycles, and deliver high power and energy densities in both aqueous and organic electrolytes. In addition to supercapacitors, the PNCM also exhibits excellent Li-storage properties in terms of high specific capacity (above 460 mA h g⁻¹ at 50 mA g⁻¹) and superior cycle stability (without any capacity decay even after 1100 cycles) when used as an anode material for lithium ion batteries.