Abstract
The objective of this work is to study the structural, magnetic and dielectric properties of 60 B2O3-10 ZnO-30-NaF: x Fe3O4 (x = 0.0 wt.%, 3.0 wt.%, 6.0 wt.%, 9.0 wt.%, 12 wt.% and 20 wt.%) glass nanocomposites. X-ray diffraction measurements indicated that the samples were amorphous except for the glass sample containing 20.0 wt.% Fe3O4, revealing the presence of a nanocrystalline magnetite phase having a cubic crystal structure with an average size of 24.10 +/- 1.79 nm. Transmission electron microscopy analysis showed that Fe3O4 nanoparticles with an average size of 24.0 nm were dispersed homogeneously inside the borate glass matrix. Fourier transform infrared spectra of these samples exhibited bands from 422 cm(-1) to 492 cm(-1) for the vibration of the Fe-O bond in the [FeO4] group and vibration modes of BO3 and BO4 units. Magnetic analysis of these glasses revealed paramagnetic-like behaviors, with a very narrow hysteresis loop and very low coercivity (H-c), close to those of typical soft magnetic materials. The relative permittivity was increased and the dielectric loss epsilon" was enhanced with increasing Fe3O4 concentration. The energy needed to move the electron from one location to infinity (W-M) increased from 0.18 to 1.28 eV with an increase in Fe3O4 content. Finally, the AC conductivity was enhanced with the addition of magnetite.