Flexible and Binder-Free Hierarchical Porous Carbon Film for Supercapacitor Electrodes Derived from MOFs/CNT

Abstract

Rational design of free-standing porous carbon materials with large specific surface area and high conductivity is a great need for ligh-weight suprecapacitors. Here, we report a flexible porous carbon film composed of metal-organic framework (MOF)-derived porous carbon polyhedrons and carbon nanotubes (CNTs) as binder-free supercapacitor electrode for the first time. Due to the synergistic combination of carbon polyhedrons and CNT, the obtained carbon electrode shows a specific capacitance of 381.2 F g^-1 at 5 mV s^-1 and 194.8 F g^-1 at 2 A g^-1 and outstanding cycling stability with a Coulombic effciency above 95% after 10000 cycles at 10 A g^-1. The assembled aqueous symmetrical supercapacitor exhibits an energy density of 9.1 Wh kg^-1 with a power density of 3500 W kg^-1. The work opens a new way to design flexible MOF-based hierarchical porous carbon film as binder-free electrodes for high-performance energy storage devices.