Metal-organic coordination polymer/multi-walled carbon nanotubes composites to prepare N-doped hierarchical porous carbon for high performance supercapacitors

Abstract

Developing high nitrogen content carbon-based electrode materials with high volumetric specific capacitance and high energy density has attracted considerable attentions for practical applications of supercapacitors. Herein, N-doped porous carbon/multi-walled carbon nanotubes (NPCMT) with high nitrogen content is prepared by directly pyrolyzing metal-organic coordination polymer (MOCP) composite, which was formed by the reaction of 4,4′-bipyridine (BPD), FeCl3 and multi-walled carbon nanotubes. The as-prepared NPCMT exhibits a hierarchical pore structure with high specific surface area (862.5 m2 g−1) and high N-doped content (10.71 at.%). Benefited from these unique properties, NPCMT presents high gravimetric specific capacitance of 295.2 F g−1, high volumetric specific capacitance of 312.9 F cm−3 and excellent cycle stability. Moreover, the assembled symmetric supercapacitors possess superior energy density of 18.82 W h kg−1. The combination of MOCP and multiwall nanotubes points toward a prominent direction to develop N-doped porous carbon electrode materials for high performances supercapacitors.