Nitrogen and Oxygen Co-doped Hierarchical Porous Carbon: Electrode Materials for High-Energy Density and Flexible Solid-State Supercapacitors

摘要

Nitrogen and oxygen co-doped hierarchically porous carbons (NO-HPCs) with robust tailored pore structures were fabricated through a soft chemistry synthetic strategy involving the use of F127 and the Friedel-Crafts alkylation reaction, referred to as NO-HPC-FH. The obtained carbon of NO-HPC-FH has rich nitrogen and oxygen contents, high surface area (up to 1715 m(2)/g), wider range pore-size distribution, and high pore volume (up to 2.8 cm(3)/g). Herein, NO-HPC-FH exhibits a high specific capacitance of 382 F/g at 0.5 A/g and an excellent cycling stability after 15 000 cycles at 20 A/g (capacitance retention is nearly 100 %), in which the contribution of the pseudocapacitance to the total specific capacitance was found to reach about 78 %. In particular, an all-solid-state flexible supercapacitor was fabricated, which also exhibited a high energy density of 33.4 Wh/kg at the power output of 879.9 W/kg, and a high cycling stability and flexibility. Therefore, this synthetic protocol using soft templates provides an alternative strategy to synthesize heteroatom-doped HPCs based on "knitted" aromatic subunits and, thus, has promising potential for application in supercapacitive materials.