Accordion-like bimetal-organic framework anchoring on the partially-exfoliated graphite paper for high-performance supercapacitors

摘要

Metal-organic frameworks (MOFs) are considered as a promising energy storage material owing to their inherent advantages of large surface area, regulatable pore size and functional groups. However, the relative poor electronic conductivity is an obstacle to their wide practical application. Herein, the partially-exfoliated graphite paper (EGP) composed of graphene nanosheets is prepared by a controlled cathodic exfoliation. EGP exhibits 3D hierarchical porous structure and good electronic conductivity, which acts as an ideal substrate for growing accordion-like structure NiCo-based bimetal-organic framework (NCMOF). The as-synthesized NCMOF/EGP shows high areal specific capacitance of 2.41 F cm(-2) at 0.5 mA cm(-2), and good rate performance of 72.6% at the current densities from 0.5 to 20 mA cm(-2). Furthermore, the constructed NCMOF/EGP//active carbon delivers an energy density of 0.11 mW h cm(-2) at a power density of 0.75 mW cm(-2), and long cycle life. The outstanding electrochemical energy storage performance of NCMOF/EGP are assigned to 3D hierarchical porous structure and good electronic conductivity of EGP combined with layered structure of NCMOF.