Ni/NiFe₂O₄@carbon nanocomposite involving synergistic effect for high-energy density and high-power density supercapattery

Abstract

In this work, a facile one step solution combustion method was applied to generate Nickel-nickel ferrite@Carbon nanocomposite using glycine as a fuel. The formation of metal ferrite@carbon phase was confirmed by x-ray diffraction, Raman and Fourier transformed infrared spectroscopy analyses. Field emission scanning electron microscope/energy dispersive x-ray analysis observations confirmed the presence of agglomerated spherical particles with uniform size distribution. The estimated pore size was in the range of 35–55 nm. High resolution transmission electron microscope analysis of the nickel-nickel ferrite@carbon nanocomposite revealed the presence of spherical nickel/ferrite grains in the size range of 13–19 nm within the carbon matrix. Ni/NiFe2O4@C was found to be electrochemically active in 1 M KOH delivering specific capacity of 1710 C g−1 at a current density of 2 A g−1. Supercapattery device were assembled using the Ni/NiFe2O4@C as positive electrode and reduced graphene-oxide (rGO) as negative electrode exhibited energy density of 62 Wh kg−1 at a power density of 3440 W kg−1 in the optimum potential window of 0–1.2 V, while the power density approached over 8000 W kg−1 at the energy density of 22 Wh kg−1. The practical applicability of the supercapattery was demonstrated by powering a commercial LED bulb.