Effect of Ni toward the optical and transport properties of the spinel solid solution NixCu1-xFe2O4 nanoparticles

The solid solutionu NixC1-xFe2O4 (x = 0, x = 0. 2, ..., x = 1) crystallizing in the spinel structure were prepared by the Sol-Gel method at 800 degrees C. The novelty of the work is also devoted to the synthesis of the spinel ferrites NixC1-xFe2O4 (0 < x < 1) using the sol gel technique and the measurement of their structural and magnetic properties by X-ray diffraction and magnetic measurements. The structural, magnetic, optical and electrical properties were investigated. The formation of the tetragonal phase with a good crystallization and stoichiometric contents were confirmed by X-ray diffraction (x = 0 and 0.2) while a transition to cubic symmetry is observed for the other compositions. NixC1-xFe2O4 exhibits n-type conduction with an increased band gap (E-g) as Ni is introduced in the crystal lattice while it decreases with augmenting the Ni-content in the cubic phase. The transport properties are characteristic of n-type behavior where the electrical conductivity decreases up to x = 0.4. Then, it increases and the conduction is mainly governed by the thermal emission over the inter-crystallites. An average hole mobility of similar to 10(-5) cm(2) V-1 s(-1) was determined for both symmetries. Magnetic measurements revealed that the saturation magnetization (Ms) increases with the Ni-content whereas the coercivity decreases. NiFe2O4 has the largest saturation magnetization (38.16 emu/g). The optical properties namely the energy gap (E-g), reflection index (n), extinction coefficient (k), dielectric complex (epsilon), optical conductivity (sigma(opt)), dissipation factor (tan delta) and relaxation time (tau) were determined.

Automated summary

Spinel ferrites NixC1-xFe2O4 were synthesized using the sol-gel method, and their structural, magnetic, optical, and electrical properties were investigated. The results showed that the conductivity and saturation magnetization of the material increased with the introduction of Ni.