Structure and optical properties of Zn and Mn co-doped nano-NiFe<inf>2</inf>O<inf>4</inf>

Abstract

Zn and Mn co-doped nano-NiFe2O4 (NFO) system was prepared by alloying NFO with ZnMn2O4 (ZMO) samples. The possibility of forming NFO single phase was examined using X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) techniques. The effects of co-doping on the crystallite size, cell parameter and cation distribution of NFO were investigated. All samples were found to be non-stoichiometric with Ni2+ excess residing at the octahedral sites. The FTIR tetrahedral band was shifted to lower wavenumbers as the amount of Zn and Mn doping increased in NFO matrix. All ions oxidation states were detected using the X-ray photoelectron spectroscopy technique. The effects of alloying between NFO and ZMO on the diffused absorbance, reflectance spectra, extinction coefficient, refractive index, dielectric constant, conductivity and direct optical bandgap energy were examined using diffused reflectance technique. The nanocomposite samples emitted UV, violet, blue and green colors with photoluminescence (PL) intensity dependent on the amount of ZMO doping in the matrix.