Influence of La doping and synthesis method on the properties of CoFe2O4 nanocrystals

Abstract

Nanocrystals of La doped CoFe2O4 were synthesized using three different techniques: flash autocombustion, citrate–nitrate and the standard ceramic technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the obtained nanocrystals. All samples were crystallized in a spinel structure with cubic symmetry. The decrease in the lattice constant was endorsed to the large difference in ionic radii of both La+3 (1.216 Å) and Fe (0.65 Å) in 6-f coordination. The citrate method displayed superior Ms values amongst all techniques. The coercivity was found to exhibit largest values for the citrate method and then the flash while smallest values are associated with ceramic technique.