Dual-doping activated carbon with hierarchical pore structure derived from polymeric porous monolith for high performance EDLC

Abstract

The fabrication of dual-doped activated carbon with a hierarchical pore structure is an effective way for the preparation of the high performance carbon-based electric double layer capacitor. Herein, nitrogen and sulfur dual-doped activated carbon (NSC) with hierarchical pore structure was obtained by directly carbonizing/activating polymer-based blend monolith. The as-obtained NSC samples exhibit a high specific surface area (1570–2550 cm2 g−1), a developed hierarchically pore structure, and have an appropriate nitrogen and sulfur content. Furthermore, originating from the synergistic effect by pore structure, heteroatom, and proper graphitized crystal structure, the optimized NSC-based electrode exhibits a high specific capacitance of 330.5 F g−1 at a current density of 0.5 A g−1, superior rate capability of 66% at 20 A g−1 and acceptable cycling stability in the three-electrode system. Meanwhile, the assembled carbon-based symmetric capacitor exhibits an acceptable energy density and a remarkable power density of 11 kW kg−1 with 6 mol L−1 KOH as the aqueous electrolyte. These results demonstrate that the as-resulting NSC could be a competitive candidate for carbon-based electrode materials, and this work would be a valuable exploration that as a facile synthetic strategy to prepared dual-doped activated carbon for electric double layer capacitor.