Effect of calcinations on the structural and magnetic properties of magnesium ferrite nanoparticles prepared by sol gel method

摘要

Magnesium ferrite nanoparticles calcined at 300 degrees C, 350 degrees C, 400 degrees C, 450 degrees C were synthesized by sol-gel method. The effects of calcinations on the cation distribution, structural and magnetic properties have been investigated. X-ray diffraction (XRD) and vibrating scanning magnetometer (VSM) were used to characterize the structural and magnetic properties. X-ray diffraction analysis revealed the formation of single phase MgFe2O4 in all the samples. Lattice constant and crystallite size increased with calcination. X-ray diffraction data were used to estimate the average cationic distribution among A site and B site. Cationic distribution shows that there is migration of cation between tetrahedral A site and octahedral B site. Saturation magnetization increased with particle size. Coercivity decreased with calcination temperature as a result of decrease in pinning effect at the grain boundary. Curie temperature (T-C) decreased slightly due to weakening of A-B exchange interaction. Low temperature magnetic measurement revealed that blocking temperature (T-B) increased due to strong magnetic interaction.