Direct decoration of Co3O4/r-GO nanocomposite on nickel foam for electrochemical energy storage applications

Abstract

Excellent electronic transport, fast ionic transport, and larger surface area are three fundamental requirements for electrode material to be suitable for advanced energy storage applications. Herein, a novel Co3O4/r-GO nanocomposite electrode material with higher specific capacitance (Csp), good rate capability, and excellent cycle performance has been prepared for electrochemical applications. The Co3O4/r-GO nanocomposite has deposited on the nickel foam (NF) via a single step in the situ hydrothermal routes. Benefiting from the excellent conductivity, higher specific surface area and electric double layer capacitance (EDLCs) of r-GO, the Co3O4/r-GO@NF electrode shows a higher Csp of 865 Fg-1 @ 1 Ag-1. The Csp of the NF supported nanocomposite show a minimum capacity loss of 17.8% on increasing the applied current density from 1 to 7 Ag-1 revealing its good rate capability. Moreover, the Co3O4/r-GO@NF electrode also shows exceptional cycling stability with 93.2% Csp-retention after 5000 cycles. The exceptional capacitive performances are benefited from the nanostructured morphology, hybrid-composition, higher surface area (173.2 m2g-1), greater electrical conductivity (9.03 × 10−3 Sm−1), and binder-free design of the prepared electrode material. All the achieved impressive electrochemical test's results prove that the Co3O4/r-GO@NF electrode is a very hopeful candidate as anode material for practical applications in the electrochemical capacitor.