Synthesis of Co-B/resin nanoparticles and heat treatment effect on their magnetic properties

The particle size and magnetic properties of Co-B nanoparticles in polymeric resin with B concentrations of 3.04 and 4.38 wt% before and after heat treatment were investigated by various techniques. X-ray diffraction results reveal that the Co-B nanoparticles are a mixture of part crystalline and part amorphous phase. Transmission electron microscopy shows that the particle size of Co-B nanoparticles encapsulated in resin is increased by the increase of Co2+ ions exchange and reduction times. Decomposition temperature of the resin is about 460 degrees C, so the heat treatment effect at 250 and 390 degrees C on their magnetic properties is also studied. X-ray diffraction and vibrating sample magnetometer results demonstrated that the crystallinity, magnetization and coercivity can be affected by heat treatment temperature. (C) 2000 Elsevier Science B.V. All rights reserved.