Ru/Co metal-organic framework nanosheets arrayed on activated carbon felt as boosted flexible electrodes for symmetric supercapacitors

Abstract

Nanosheet configurations of metal-organic frameworks (MOFs) have received considerable attention for the development of high-performance supercapacitors (SCs). Solvothermal synthesis of 2D RuCo-MOF nanosheets (nanosheet thickness up to ~100 nm) arrayed on 3D activated carbon felts (ACFs) allows us to fabricate high-performance electrodes with a well-defined porosity. The binder-free RuCo-MOF/ACF electrode provides an excellent specific capacitance of 2219.7 mF cm−2 at a current density of 1.0 mA cm−2. Notably, the RuCo-MOF/ACF: RuCo-MOF/ACF symmetric supercapacitor (SSC) device delivers a high energy density of 10.66 Wh cm−2 at a favorable power density of 27.69 W cm−2, and a remarkable cyclability with the capacity retention of 94.7 % after 6000 continuous cycles. The results suggest that the energy storage performance can be significantly improved by introducing the Ru active center (1.2 at. %) into Co-MOF. The findings of this work demonstrate a cost-effective approach to the development of MOF materials with excellent charge storage capabilities for next-generation supercapacitors.