Enhancement of elastic, optical and opto-electrical properties of Ni-Substituted CoFe2O4 nanoparticles with different concentrations

This study examined the influence of the addition of Ni ions to nano-ferrite with general formula; NixCo1-xFe2O4 (where, x = 0.0, 0.3, 0.5, 0.7 and 1.0), which was synthesized using the coprecipitation technique. The analysis of XRD and FTIR analyses suggest the formation of the single-phase cubic structure for all samples. The average crystallite size of the prepared specimen was computed at 36 nm using the Scherer equation. The force constants for the tetrahedral and octahedral sites were well-estimated using FTIR data. Hence, longitudinal, transverse (shear), mean elastic sound wave velocities were calculated. Thus, Elastic moduli such as Young's modulus, stiffness constant, bulk modulus, modulus of rigidity, Poisson ratio and Debye temperature were determined. The variation of these parameters for all synthesized samples has been explained in terms of binding forces between ions of the spinel lattice. In addition, reflectance and transmittance have been used to investigate the optical properties. Both calculated refractive index, n, and the absorption index, k, have been used to estimate, the high-frequency dielectric constant, lattice dielectric, complex dielectric constant, volume and surface energy loss functions, dielectric relaxation time and complex optical conductivity as well as optical electronegativity. Moreover, Drude theory was applied to investigate the opto-electrical parameters, such as optical carrier concentration, optical mobility, optical resistivity, and the non-linear optical parameters. Finally, the electronic transitions of all studied concentrations were estimated.