Structural and optical properties of nanosized Co substituted Ni ferrites by coprecipitation method

ABSTRACT

Nano crystalline powder of Co–Ni ferrites compounds having the chemical formula Ni_1-xCo_xFe₂O₄ with x = 0.0, 0.25, 0.5, 0.75 and 1.0 were prepared by co-precipitation method. The nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Scanning Electron Microscopic (SEM) techniques. XRD studies confirmed the formation of single phase spinel structure with space group of $\mathrm{F}\mathrm{d}\overline{3}\mathrm{m}$. Debye-Scherrer method was applied to determine average crystallite size and the value was found to be in the range of 23–66 nm. Elemental composition characterizations of the prepared samples were performed by Energy Dispersive Spectroscopy (EDS) which shows the presence of Ni, Co, Fe and O. The optical band gap (E_g) of Ni–Co ferrite samples was determined by means of UV–visible spectra. The optical band gap of the prepared samples have been calculated using Tauc plots and have been found to decrease with increase in Co²⁺ content from 3.66 to 3.58 eV.

KEYWORDS:

• Ni–Co ferrite
• XRD
• SEM
• FTIR
• optical properties

Acknowledgements

We are also grateful to CIF, IIT and Chemistry department, Institute of Science BHU for technical supports.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Preeti Lahiri http://orcid.org/0000-0001-8488-8067

Additional information

Funding

The authors greatly acknowledge the Council of Scientific and Industrial Research (CSIR), New Delhi to provide financial support (09/013(0637)/2016-EMR-1) for this investigation.