• Mitoseriu, Liliana
• Airimioaei, Mirela
• Ciomaga, Cristina Elena
• Schileo, Giorgio
• Neagu, Alexandra Maria
• Tascu, Sorin
• Galassi, Carmen

Abstract

<jats:p>Particulate composites of ferrite and ferroelectric phases with xNiFe2O4 (NF) and (1 − x)Pb0.988(Zr0.52Ti0.48)0.976Nb0.024O3 (where x = 2, 10, 20, 30, 50, 70, and 100 wt. %) were prepared in situ by sol-gel method. The presence of a diphase composition was confirmed by X-ray diffraction while the microstructure of the composites was studied by scanning electron microscopy revealing a good mixing of the two phases and a good densification of the bulk ceramics. The dielectric permittivity shows usual dielectric dispersion behavior with increasing frequency due to Maxwell-Wagner interfacial polarization. AC conductivity measurements made in frequency range 1 Hz-1 MHz suggest that the conduction process is due to mixed polaron hopping. The effect of NF phase concentration on the P-E and M-H hysteresis behavior and dielectric properties of the composites was investigated. At low NF concentration a sharp ferro-paraelectric transition peak can be observed at around 360 °C while for higher NF concentrations a trend to a diffuse phase transition occurs. All the composite samples exhibit typical ferromagnetic hysteresis loops, indicating the presence of ordered magnetic structure.</jats:p>

Topics

• impedance spectroscopy
• dispersion
• phase
• scanning electron microscopy
• x-ray diffraction
• composite
• phase transition
• ceramic
• interfacial
• densification
• dielectric dispersion