Fe₂O₃ Embedded in N-Doped Porous Carbon Derived from Hemin Loaded on Active Carbon for Supercapacitors

Abstract

The high power density and long cyclic stability of N-doped carbon make it an attractive material for supercapacitor electrodes. Nevertheless, its low energy density limits its practical application. To solve the above issues, Fe2O3 embedded in N-doped porous carbon (Fe2O3/N-PC) was designed by pyrolyzing Hemin/activated carbon (Hemin/AC) composites. A porous structure allows rapid diffusion of electrons and ions during charge–discharge due to its large surface area and conductive channels. The redox reactions of Fe2O3 particles and N heteroatoms contribute to pseudocapacitance, which greatly enhances the supercapacitive performance. Fe2O3/N-PC showed a superior capacitance of 290.3 F g−1 at 1 A g−1 with 93.1% capacity retention after 10,000 charge–discharge cycles. Eventually, a high energy density of 37.6 Wh kg−1 at a power density of 1.6 kW kg−1 could be delivered with a solid symmetric device.

Keywords

• Hemin/AC
• Fe₂O₃/N-PC
• pseudocapacitance
• quasi-solid-state supercapacitor