Highly efficient asymmetric supercapacitor-based on Ni-Co oxides intercalated graphene as positive and Fe2O3 doped graphene as negative electrodes

Asymmetric supercapacitor (ASC) technique is introduced as promising and efficient energy storage devices due to their fast charging process and high-power density. A simple and green approach was introduced to fabricate mixed Co3O4/NiO intercalated reduced graphene oxide (rGO) nanosheets as ternary nanocomposite electrode materials for ASC applications. Herein, a Co3O4/NiO/rGO ternary nanocomposite was successfully fabricated using a hydrothermal method. The field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were utilized to elucidate the morphological shape and chemical surface analysis for the fabricated materials. Comparing the prepared samples, the ternary nanocomposite demonstrated a good capacitance value of 485.6 F/g at a current density of 2 A/g, good cycling stability, and low equivalent series resistance. The ASC was assembled using the Co3O4/NiO/rGO electrode as positive electrode and Fe2O3/rGO binary composite as the negative electrode. The proposed configuration design of ASC achieved a high energy density (37.83 W h/kg) at a high-power density of (750 W/kg) and a long life-time (86.9%) of over 6000 cycles. The ASC configuration design of Co3O4/NiO/rGO nanocomposites//Fe2O3/rGO opens new doors for promising green, economic, and efficient material-based supercapacitors.

Automated summary

The Co3O4/NiO/rGO ternary nanocomposite was successfully fabricated using a hydrothermal method, showing good capacitance value, cycling stability, and low equivalent series resistance. The assembled ASC with Co3O4/NiO/rGO electrode as positive electrode and Fe2O3/rGO binary composite as negative electrode achieved high energy density, high-power density, and long life-time, opening new doors for promising green, economic, and efficient material-based supercapacitors.