LAUSR

Abstract Co3O4-NiO based nanocomposite films were electrochemically deposited onto FTO glass substrates in aqueous solutions containing different mole ratio of cobalt (II) and nickel (II). The structural characteristics of the films examined by X-ray diffraction reveal that the Co3O4 cubic phase dominates over the NiO cubic phase in the composite films. Field emission scanning electron micrographs show that the composite films 1C1NO (Co/Ni mole ratio 1:1) and 2C1NO (Co/Ni mole ratio 2:1) have the porous nanofibers-like structure and the porous nanorods-like structure, respectively. The nanocomposite films exhibit the synergistic effect of both metal oxides, resulting in a significantly higher specific capacitance. The cyclic voltammetry measurements show that the 2C1NO film has the optimum specific capacitance values of 256 and 233.3 Fg−1 at the scan rates of 10 and 20 mVs−1, respectively. However, at higher scan rates of 50 and 100 mVs−1, the 1C1NO composite film exhibits the optimum specific capacitance. The galvanostatic charge-discharge measurements show that the 2C1NO composite film has the highest specific capacitance (267.2 Fg−1) and energy density (6.48 Whkg−1) at the current density of 1 mAcm−2, whereas it exhibits the highest power density (6885.36 Wkg−1) at 3 mAcm−2 current density.