Structural and optical properties of nanosized Co substituted Ni ferrites by coprecipitation method
Chanda Kumari, Hemant Kumar Dubey, Farhana Naaz, Preeti Lahiri
Abstract
Nano crystalline powder of Co–Ni ferrites compounds having the chemical formula Ni1-xCoxFe2O4 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 Fd3¯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 (Eg) 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.