Abstract
Oleylamine (OAm) functionalized NiFe2 O (4) nanoparticles were synthesized by reflux method. Oleylamine as a multufunctional ligand provides the essential basic condition for the formation of NiFe2 O (4) nanoparticles, and it has also surfactant and reducing agent roles. The product was characterized by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry, and thermal gravimetric analyzer (TG). The detailed electrical conductivity and dielectric property of measurements have been performed by dielectric impedance analyzer. The conductivity results show that ac conductivity (sigma (ac)) is temperature dependent particularly at low frequencies whereas dc conductivity (sigma (dc)) exhibits only temperature dependency. The highest dc conductivity is 4.37 x 10 (-12) S.cm (-1) at 120 C-a similar to. The dielectric constant (epsilon (')), dielectric loss (epsilon (aEuro3)), and dielectric loss tangent (tan delta) show different behaviors with frequency and temperature. The variation of dielectric properties with temperature is mainly due to temperature-assisted electron exchange between Ni (2+) and Fe (3+) ions.