Synthesis of coprecipitated strontium hexaferrite nanoparticles in the presence of polyvinyl alcohol

Strontium hexaferrite (SrFe(12)O(19)) nanoparticles were synthesized by the chemical coprecipitation method and using polyvinyl alcohol (PVA) as a protective agent. The synthesized samples were characterized by differential thermal analysis, X-ray diffraction, scanning and transmission electron microscopy, particle size analyzer, sedimentation test and vibrating sample magnetometer. In the presence of PVA, the single-phase SrFe(12)O(19) nanoparticles were obtained at low temperature of 650 degrees C. The average particle size of SrFe(12)O(19) precursor was 15 nm, which increased to 61 nm after calcination at 650 degrees C. The magnetic measurements indicated that PVA decreased coercivity from 4711 to 3216 Oe with particle size reduction. The results showed that PVA as a protective agent could be effective in decreasing the particle size, calcination temperature and coercivity of SrFe(12)O(19) nanoparticles. (C) 2011 Elsevier B.V. All rights reserved.