Hierarchical double-shelled frameworks of polyaniline@N-doped porous carbon for supercapacitors

Abstract

Conductive polymer and porous carbon hold critical promise as capacitive materials. However, individual use of these materials seriously limits their applications due to poor rate capability and short lifetime or low capacitance. Herein, we successfully fabricate hierarchical polyaniline@N-doped porous carbon (PANI@NPC) double-shell frameworks by in-situ coating of PANI on the NPC surface, and achieve high charge-storage performance. The whole design involves multiple strategies of nanostructurization, constructing hierarchical structure, and hybridization, which will address the above electrochemical concerns. The best specific capacitance for PANI@NPC-2 with 32% NPC reaches 660.0 F g−1 at 0.5 A g−1 and remains 479.8 F g−1 at 5 A g−1, significantly higher that the results of PANI and other hybrids. Moreover, the symmetric supercapacitor using PANI@NPC-2 electrodes demonstrates good performance with an energy density of 8.0 Wh kg−1 at 0.5 A g−1 and a power density of 1750.0 W kg−1 at 10 A g−1. The promoted performance relies largely on the synergy of desirable properties of building blocks in hybrids. This research manifests a general yet efficient method for high-performance hybrid materials for promoting the development of sustainable energy.