Fe/Co doped ZIF derived nitrogen doped nanoporous carbon as electrode material for supercapacitors

Nanoporous carbon (NPC) for electrochemical energy storage devices has gained much interest due to its high specific area and tunable porosity. Herein, Fe and Co co-doped NPC is synthesized by a simple co-precipitation method followed by carbonization of Fe and Co doped ZIF8 at 900 ℃ (Fe-Co/NPC-900). The structural, morphological, elemental, chemical bonding, surface area, and thermal degradation of the synthesized material have been evaluated using X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller method, and thermogravimetric analysis, respectively. The high surface area of 933 m²/g and nanoporous structure of Fe-Co/NPC-900 electrode results in a high specific capacitance of 900 F/g at a current density of 5 A/g. The cycle performance of Fe-Co/NPC-900 was remarkable with 88% of the capacitance retention after 5000 cycles at a high current density of 30 A/g. The high electrochemical performance of Fe-Co/NPC-900 is attributed to the hybrid doping of Fe and Co in nitrogen doped carbon network which offers a synergic effect in reaction.