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

Abstract 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 Co 2+ ions exchange and reduction times. Decomposition temperature of the resin is about 460°C, so the heat treatment effect at 250 and 390°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.