Structural effect on Magneto-electric properties in (1-x) BiFe0.9La0.1O3 + xNi0.6Zn0.4Fe1.94V0.06O4 composites

Abstract

Enhancement of magnetic as well as electric properties in BiFe0.9La0.1O3 (BLFO) with the addition of Ni-Zn ferrite have been studied on the compositions (1-x)BiFe0.9La0.1O3 + xNi0.6Zn0.4Fe1.94V0.06O4 (where, x = 0, 0.1, 0.2, 0.3, 0.5, 0.7 and 1.0). The samples were synthesized by the conventional ceramic methods sintered at 850 °C for 2 h. XRD studies revealed a normal distorted rhombohedral phase (R3c space group), cubic phase (Fd-3 m space group) and some impurity phases like Bi2Fe4O9 and Bi25FeO39 in the synthesized composites. The addition of Ni0.6Zn0.4Fe1.94V0.06O4 (NZVFO) successfully eliminated Bi25FeO39 phase from the derived composites. The average grain sizes (Dg) were estimated from FESEM images and found to decrease with the increase of NZVFO content in the samples. There is a large increment in saturation magnetization (MS) from 0.1 emu/g to 50.5 emu/g for adding NZVFO in BLFO. The frequency-dependent magnetic permeability μ and dielectric constant ε and dielectric loss tanδε have been measured with an impedance analyzer. The addition of NZVFO results in decreasing the permittivity ε' and dielectric loss (tanδε). The composites with 0.7 NZVFO addition shows a stable matching impedance Z/η0≈0.5 over a wide frequency range (5–70 MHz), demonstrating its possible applications in miniaturizing devices such as microwave antenna.

Keywords

• Multiferroics
• Matching impedance
• Saturation magnetization
• Surface porosity
• Permeability