Influence of Nd-Co Substitution on Structural, Electrical, and Dielectric Properties of X-Type Hexagonal Nanoferrites

A series of single phase X-type hexagonal ferrites with concentration Sr2-x Nd (x) Ni2Fe28-y Co (y) O-46 (x = 0.02, 0.04, 0.06, 0.08, 0.10 and y = 0.1, 0.2, 0.3, 0.4, 0.5) has been prepared by sol-gel method sintered at 1250 A degrees C for 6 h. The x-ray diffraction analysis reveals the single phase of X-type hexagonal ferrites. The particle size was calculated by using SEM and TEM. The ferrite substituted with Nd3+ and Co2+ has average particle size in the range of 40-50 nm. The room temperature electrical resistivity experiences the significant enhancement from a value of 1.1 x 10(7) to 2.03 x 10(8) abroken vertical bar cm with the increase in Nd3+ and Co2+ concentration. The dielectric constant exhibits high value at low frequencies and decreases with the increase of frequency. The tangent dielectric loss shows the abnormal behavior which can be explained on the basis of hopping between the Fe2+ and Fe3+ ions on octahedral sites. The maximum value of tangent loss at low frequencies reflects the application of these materials in medium frequency devices (MF).