ACTA

Phase Evolution of Iron Nanoparticles Subjected to Thermal Treatment

K. Brzózka^a, M. Krajewski^b, T. Szumiata^a, B. Górka^a, M. Gawroński^a, T. Kaczor^a, W.S. Lin^c, H.M. Lin^c
^aUniversity of Technology and Humanities, Faculty of Mechanical Engineering, Department of Physics, E. Stasieckiego 54, 26-600 Radom, Poland
^bInstitute of Fundamental Technological Research, Polish Academy of Sciences, A. Pawińskiego 5B, 02-106 Warsaw, Poland
^cTatung University, Department of Materials Engineering, Taipei 104, Taiwan, ROC

Full Text PDF

Magnetic nanoparticles based on iron or iron oxides represent an excellent nanomaterial in respect of their fundamental research as well as numerous applications. This work presents a Mössbauer study of the influence of thermal treatment on the structure and phase composition of iron nanoparticles fabricated via a simple reduction reaction. Identification of iron-containing phases has been carried out for the series of samples annealed at different temperatures ranging between 200° and 800°. Both crystalline and amorphous iron as well as variety of iron oxides have been detected. It has been proved that the nanoparticles annealed at 500° show superparamagnetic behavior as a result of ultrafine sizes of crystallites of iron oxides that arise in the oxidation processes.

DOI:10.12693/APhysPolA.134.1015
PACS numbers: 61.05.Qr, 61.46.Df, 75.50.Tt, 75.75.Cd, 81.07.-b