Metal-organic framework derived nickel‑cobalt layered double hydroxide nanosheets cleverly constructed on interconnected nano-porous carbon for high-performance supercapacitors

Abstract

The ingenious use of renewable and degradable biomass glucose materials to replace traditional organic synthetic materials can create huge economic benefits and potential ecological environmental protection. In this work, interconnected nano-porous carbon/nickel‑cobalt layered double hydroxide (INPC/NiCo-LDH) composites were successfully fabricated through calcination and solvothermal techniques, by first depositing 2-methylimidazole cobalt salt (ZIF-67) nanoparticles on the surface of INPC using glucose as the carbon source, followed by an in situ growth of NiCo-LDH nanosheets by controlling ion etching and co-deposition. The obtained INPC/NiCo-LDH composite exhibited high mass capacitance (1712 F g−1 at 0.5 A g−1), good rate capability and cycling performance (86.1 % after 5000 cycles). The assembled INPC/NiCo-LDH//INPC asymmetric supercapacitor (ASC) showed excellent capacitive performance (115.9 F g−1 at 0.5 A g−1) and high energy density (41.2 Wh kg−1 at 400 W kg−1). The three prefabricated all-solid-state INPC/NiCo-LDH//INPC ASCs linked in series could successfully light up a small light bulb, showing a potential application in real life.