Author(s)

Naraavula Suresh Kumar¹, Katrapally Vijaya Kumar^2*

¹Mallareddy Institute of Engineering & Technology, Secunderabad, TS, India.
²Department of Physics, JNTUH College of Engineering Jagtial, Nachupally, Karimnagar-Dist, TS, India.

Bismuth substituted cobalt nano ferrites with the chemical composition Co Bi_x Fe_2-x O₄ (x = 0.00, 0.05, 0.10, 0.15, 0.20 & 0.25) were prepared by sol-gel combustion method. The phase identification of prepared samples is characterised by X-ray powder diffraction (XRD) method, which confirms the formation of a single phase fcc spinal structure. The mean crystallite sizes of all prepared samples were obtained within the range of 21 (±5) nm. Transmission Electron Microscopy (TEM) images also confirmed the crystallite size of all the synthesised samples was in nano range. With the effect of Bi³⁺ ion substitution on spinal cobalt ferrite, the magnetic properties were investigated by using Vibration Sample Magnetometer (VSM). The obtained hysteresis (M-H) curves of all the samples were analysed under the applied magnetic field of range ± 10 K Oe at 300 K. The magnetic properties such as saturation magnetisation (M_s), remnant magnetization (M_r) and coercivity (H_c) values are tabulated, which show a decrease in trend as the bismuth ion concentration increases. This is due to the addition of Bi³⁺ ion in the place of Fe³⁺ ion (octahedral site) and hence the Bi³⁺-Fe³⁺ ion interaction predominates as compared with the Fe²⁺-Fe³⁺ ion interaction. The data obtained from magnetic studies, the variation among the magnetic properties have been investigated for all the prepared samples.

Bi-Co Nano Ferrites, Sol-Gel Combustion Method, TEM and VSM

Kumar, N. and Kumar, K. (2016) Effect of Bi3+ Ion Substitution on Magnetic Properties of Cobalt Nano Ferrites Prepared by Sol-Gel Combustion Method. Soft Nanoscience Letters, 6, 37-44. doi: 10.4236/snl.2016.63004.