Fabrication, characterization, exchange coupling and magnetic behavior of CoFe2O4/CoFe2 nanocomposite nanofibers

CoFe2O4/CoFe2 nanocomposite nanofibers (NFs) with superior magnetic performance have been fabricated using electrospinning technique combined with hydrogen-thermal reduction reaction. A detailed study on the evolution of structural, morphological and magnetic properties with reduction temperature is undertaken. It is found that these composite NFs exhibit a good single-phase magnetic behavior, indicating that the magnetically hard CoFe2O4 and soft CoFe2 phases in them are sufficiently exchange coupled. The composition dependence of magnetic properties of CoFe2O4/CoFe2 composite NFs is obviously different from the reported nanopowder and microfiber counterparts. Furthermore, a higher remanence and maximum energy product can be achieved for CoFe2O4/CoFe2 composite NFs.