MOF-derived hierarchical carbon network as an extremely-high-performance supercapacitor electrode

Abstract

Electric double-layer capacitor (EDLC), as one type of supercapacitor, holds great promises for fast-charging energy storage devices but suffers from limited specific capacitance. The design and development of high performance EDLC-type carbon materials with the effective synergistic effect of high conductivity, tailored porous structure, and high surface area still remain challenging. Here, we report a novel hierarchical porous carbon with a combination of highly conductive electronic pathways and rich ionic storage units in three-dimensional network morphology, leading to high specific capacitance of EDLC. Specifically, by facile hydrothermal synthesis and carbonization, the carbon electrode derived from metal-organic framework and polymer fibers, exhibits extremely high specific capacitance of ∼ 385 F g−1 at 0.1 A g−1 and can still maintain capacitance of 303 F g−1 at 10 A g−1. The high electrochemical performance can be attributed to the rich network of micro and mesoporous structures for electrolyte transport and ion adsorption as well as highly conductive electronic pathways inside the electrodes. The assembled EDLC thus delivers a high energy density of 10.51 Wh kg−1 and a power density of 5.454 kW kg−1 at the current density of 10 A g−1 in the aqueous electrolyte. Hence, the present study is expected to open a promising route to developing porous materials for high-performance energy devices.