CoFe2O4@methyl cellulose core-shell nanostructure and their hybrids with functionalized graphene aerogel for high performance asymmetric supercapacitor

Abstract

Recently, the use of asymmetric supercapacitors (ASC) has attracted much attention due to their optimum storage of energy and a high range of voltage. Here, we have indicated the design and fabrication of a unique ASC based on metal-spinel core-shell nanocomposite (CoFe2O4@MC) as a positive electrode and a p-phenylenediamine (PPDA)-graphene aerogel composite (AP) as a negative electrode in aqueous KOH electrolyte solution. The CoFe2O4@MC nanocomposite was prepared by the chemical deposition method. The AP was also effortlessly organized using the hydrothermal method. Considering the incorporation of methylcellulose carbohydrate polymer (MC) into the CoFe2O4 nanomaterial and consequently having a porous structure, a specific capacitance of 433.3 F g−1 was obtained at the current density of 1 A g−1 with the configuration of three electrodes. The CoFe2O4@MC//AP-ASC operates in the voltage range up to 2.3 V and provides a specific capacitance of 99 in 1 A g−1. It presents an impressive energy density and power density of ~73 W h Kg−1 and 1056 W kg−1, respectively which prove its quality. The most important feature seems to be good cycling stability and capacity retention of 89% after 2000 cycles. These splendid outcomes show that CoFe2O4@MC nanocomposite possibly seems to be a satisfying choice for the next generation of devices with the capability of energy storage.