Fabrication and characterization of magnetic FePt nanoparticles prepared by extraction–pyrolysis method

V. Serga, M. Maiorov, A. Cvetkovs, A. Krumina, A. I. Popov

Abstract


In the present work, possibilities of the extraction–pyrolysis method (EPM) to produce FePt nanoparticles with the face-centered tetragonal (fct) phase were studied. A mixture of fine-disperse powder of carbonyl iron and n-trioctylammonium hexachloroplatinate [(С8Н17)3NH]2PtCl6 solution in toluene, preliminary produced by the solvent extraction method, is used as a precursor. Precursors with a different molar ratio of metals were used. The performed investigations show that as a result of pyrolysis in the air (Tpyr = 600°C, tanneal = 30 min), a FePt alloy with the fct phase is produced. Moreover, such phases as FePt3 and/or Fe3Pt with the cubic structure may be also present in the final products. The phase composition of the produced samples depends on the Fe:Pt molar ratio in the precursor. An increase of the fct phase part with the growth of the iron content from 40 to 60 mol% is observed. Also, with the Fe80%Pt20% molar ratio of the metals in the precursor, only the ordered fct phase along with a small amount of hematite and iron chloride exists in the produced sample. Magnetic measurements confirm the fct-FePt phase formation in all produced samples and evidence that the coercivity exceeds the value (3 kOe) at the 50 mol% Fe concentration in the precursor and significantly decreases with increasing the Fe concentration to 80 mol%.

Keywords


FePt alloy; extraction–pyrolysis method; Fe/Pt composition; high magnetic coercivity

Full Text:

PDF


DOI: https://doi.org/10.6001/chemija.v29i2.3713

Refbacks

  • There are currently no refbacks.


ISSN 0235-7216 (Print)
ISSN 2424-4538 (Online)