Fabrication of SmCox Nanoparticles as a Potential Candidate of Materials for Super-high-density Magnetic Memory: Use of Gold as the Third Element

The SmCo5 magnetic nanoparticles were prepared via simultaneous reduction of Sm(acac)3·xH2O, Co(acac)3, and AuCl in tetraethylene glycol (TEG) in the presence of stabilizing agents. The presence of Au is considered to promote the formation of SmCox (x=5–8.5) nanoparticles. As-prepared SmCox nanoparticles had an average diameter of 6.9 nm and a structure similar to CaCu5 crystal. Magnetic measurements of these particles exhibited a coercivity (Hc) of 1500 Oe at 300 K.