Enhancement of electrical conductivity and dielectric constant in Sn-doped nanocrystlline CoFe2O4

Abstract

We have investigated the dielectric constant and capacitance of pure and tin-doped cobalt ferrite nanoparticles. The nanoparticles with spinel structure were synthesized by chemical co-precipitation method. The average particle size of the samples was 20 +/- 2 nm. Room temperature impedance spectroscopy of the nanoparticles was performed in the frequency range of 100 Hz-2 MHz. The conductivity and dielectric response of the nanoparticles were found to increase with tin doping (20 % by atoms) in cobalt ferrite nanoparticles. The observed value of high-dielectric response at low frequencies has been attributed to the presence of grain boundaries in these nanoparticles.