Comparison of carbon aerogel and carbide-derived carbon as electrode materials for non-aqueous supercapacitors with high performance

Two porous carbon materials, one synthesised by pyrolysis of an organic aerogel prepared using sol–gel method and the other synthesised from molybdenum carbide by high temperature chlorination method, were tested as supercapacitor electrode materials in a non-aqueous tetraalkylammonium salt-based electrolyte. The gravimetric capacitance values calculated for the carbon aerogel (CAG)-based system were almost two times smaller (~55 F g−1) compared to carbide-derived carbon (C(Mo2C))-based system (~125 F g−1). However, due to the very wide region of ideal polarizability, 3.6 V for C(Mo2C) and 3.8 V for CAG-based test cells, very high energy densities up to 63 Wh kg−1 (34 Wh dm−3) and power densities up to 757 kW kg−1 (314 kW dm−3) were estimated for these systems, respectively. CAG-based system shows very short characteristic charge/discharge time constant values (0.05 s).