Mossbauer studies of La-Zn substitution effect in strontium ferrite nanoparticles

Many studies on cation substitution have been carried out in sintered magnets application, since intrinsic magnetic properties such as saturation magnetization depend on the cation configuration in the M-type hexagonal structure. La-Zn substituted Sr-ferrite nanoparticles were fabricated by a sol-gel method. Their magnetic and structural properties were characterized by using the XRD, VSM, TG/DTA, and Mossbauer spectroscopy. We focused on the Mossbauer effects of non-magnetic ions such as the Zn occupation of 4f(1) and 2b sites in the M-type hexagonal structure. As Substitution x increased, the saturation magnetization increased, and took a maximum at x = 0.2 before decreasing again. We interpret that it is closely related to Zn occupation of 4f(1) and 2b. This was thought to be caused by the preferential location of Zn2+ at the down-spin Fe3+ site. (c) 2004 Elsevier B.V. All rights reserved.