Fe₂O₃ Nanoparticles Decorated on Graphene-Carbon Nanotubes Conductive Networks for Boosting the Energy Density of All-Solid-State Asymmetric Supercapacitor

Abstract

Ferric oxide (Fe2O3) has drawn massive attention as a promising cathode electrode material for supercapacitors because of its large theoretical specific capacity, low cost, and abundance in nature. Nevertheless, its relatively low conductivity and large volume change seriously impede its electrochemical performance. Herein, Fe2O3 nanoparticles decorated on graphene-carbon nanotubes (CNTs) conductive networks (Fe2O3/GNs/CNTs) were prepared by a simple reflux way. Owing to the unique structure, the Fe2O3/GNs/CNTs electrode delivers a notably enhanced specific capacity (675.7 F g–1 at 1 A g–1) and superior rate characteristic in 6 M KOH aqueous electrolyte. More importantly, the as-constructed all-solid-state asymmetric device using Fe2O3/GNs/CNTs as the cathode electrode and sulfurized CoAl layered double hydroxides (SLDH) as the anode electrode shows the high energy density of 60.3 Wh kg–1 and good electrochemical steadiness in KOH/PVA gel electrolyte. Therefore, this strategy provides a novel mothed to synthesize Fe2O3 based electrode materials for energy storage system.