N-doped Hierarchical Mesoporous Carbon from Mesophase Pitch and Polypyrrole for Supercapacitors

摘要

N-doped hierarchical mesoporous carbons have been fabricated by using mesophase pitch (MP) as a carbon precursor and polypyrrole as a nitrogen resource through the MCM-48 template. Carbonization temperature plays a key role in the morphology, mesoporous structure, and electrochemical properties of N-doped porous carbons (NPCs). At an appropriate carbonization temperature (700 degrees C), as-prepared NPC-700 exhibits rich nitrogen content (4.48 wt %), medium specific surface area (495.9 m(2) g(-1)), and high specific capacitance of 232.2 F g(-1) at a current density of 2 A g(-1) in a three-electrode system. Due to the generation of pseudocapacitance, the specific capacitance of NPC-700 is 53.6 F g(-1) higher than that of PC-700 without polypyrrole. In addition, NPC-700 shows high specific capacitance of 110.6 F g(-1) at a current density of 0.2 A g(-1), a good capacitance retention of 77.8% at the current density of 5 A g(-1), and the large energy density of 15.30 Wh kg(-1) at a power density of 399.9 W kg(-1) in a two-electrode system. This work provides a novel example of how N-doped porous carbons derived from mesophase pitch and polypyrrole can be used as a promising electrode material for potential energy storage applications.