Porous reduced graphene oxide paper as a binder-free electrode for high-performance supercapacitors

Abstract

A facile template approach is developed to prepare highly conductive and flexible reduced graphene oxide (rGO) paper with hierarchical porous structures. When used as an electrode for a capacitor, these porous carbon layers demonstrate an enhanced electrochemical performance due to their large ion-accessible surface area and efficient electrolyte-ion transport pathways. The porous rGO electrode delivers a specific capacity of 173.5 F g⁻¹, almost 1.8 times higher than 95.1 F g⁻¹ of packed rGO. More importantly, the porous electrode also exhibits a good electrochemical performance with an energy density of 28.5 W h kg⁻¹ and power density of 4000 W kg⁻¹, as well as excellent cycling stability with 101.5% of its initial capacitance after 2000 charge–discharge cycles at a current density of 5 A g⁻¹.