Comparative analysis of physico-chemical properties of NiCo2O4 and corresponding individual metal oxides

Abstract

Abstract Nano/micro-sized spinel mixed metal oxides with stoichiometry MxN3-xO4 have received great attention in the past decade because of their broad application prospects in energy storage devices. Among the various spinel mixed metal oxides, nickel cobaltite (NiCo2O4) is significantly researched due to its outstanding advantages including large specific surface area, high permeability, short electron and ion diffusion pathways, ease of synthesis and many more. Keeping these characteristics in mind, NiCo2O4 has been synthesized via a facile, quick and low-cost combustion method. Structural and morphological properties of as-synthesized NiCo2O4 were compared with the corresponding individual metal oxides viz. NiO and Co3O4 synthesized through the same method. Nano/micro-sized NiCo2O4, NiO and Co3O4 were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy. XRD confirmed face-centered cubic phase for the NiCo2O4 in which Ni occupies octahedral sites while Co is distributed in both octahedral and tetrahedral sites. FESEM revealed the cubic nanostructures of the oxides. The compositional ratio of 1:2 for Ni and Co was calculated from the EDS analysis for the NiCo2O4. A high degree of purity was also ascertained for NiCo2O4, NiO and Co3O4 by EDS analysis. Finger-print region (500-600 cm-1) FTIR peaks for all the synthesized materials confirmed the formation of the metal-oxygen (M-O) bonds.