Solvothermal synthesis of Sm3+-doped Fe3O4 nanoparticles

Magnetic iron oxide nanoparticles doped with samarium were prepared by solvothermal polyol method. An introduction of 2,2′-bipyridine during the synthesis reduces the particle diameter to about 9nm in average. The difference in physical and magnetic properties of the samples prepared with and without capping agent was outlined on the basis of complex characterization by a number of experimental techniques. The characteristics of resulted product make it suitable for biomedical applications, for instance, as a contrast agent for MRI. •Sm3+-doped magnetite nanoparticles were obtained by solvothermal polyol method.•Magnetic nanoparticles are twice smaller if 2,2′-bipyridine is used as a capping agent.•Sm3+-doped magnetite nanoparticles have clean surface and are useful as a MRI contrast agent.