Polymerization-Pyrolysis-Derived Hierarchical Nitrogen-Doped Porous Carbon for Energetic Capacitive Energy Storage

Abstract

Nitrogen-doped porous carbons are attractive electrode materials for supercapacitors because of their high specific capacitance and desirable surface property. Here, we report a facile polymerization-pyrolysis strategy to construct hierarchical porous carbon, which is rich in surface redox nitrogen species. The polymeric precursor of phenolic resin cross-linked with polyaniline is produced by a mild hydrothermal process. The following calcination procedure yields hierarchical nitrogen-doped porous carbon, which presents a large specific surface area of 968.5 m 2 g −1 with multi-scale porous structures including micro-, meso-, and macropores. It is found that pyrrolic nitrogen and oxidized nitrogen are successfully introduced on the porous carbon surface, and they can supply extra pseudo-capacitance. The synergy of massive charge storage sites and interconnected ion transport channels enables the hierarchical nitrogen-doped porous carbon to exhibit a high specific capacitance of 320.6 and 250.0 F g −1 in the alkaline electrolyte at current densities of 0.5 and 100 A g −1 , respectively. In addition, the assembled symmetrical supercapacitor with organic electrolytes shows a huge energy density of 48.9 Wh kg −1 at a power density of 375.0 W kg −1 , with a capacitance retention close to 100% after 50,000 cycles.

In Situ Self-Assembly of Nitrogen-Doped 3D Flower-like Hierarchical Porous Carbon and Its Application for Supercapacitors

“…The results showed the degree of graphitization and defect for the D, D″, and G bands. Meanwhile, the I band showed the linkage between heteroatom (N) into the carbon walls, corresponding to XPS and EDS [ 44 , 45 ].…”