Phase transition, structural and magnetic parameters of vanadium-substituted Bi_0.9Sm_0.1FeO₃ multiferroic ceramics

ABSTRACT

The inorganic multiferroic compounds Bi_0.9Sm_0.1Fe_1 − xV_xO₃ (x = 0.0, 0.015, 0.03, and 0.045) were prepared by the solid-state reaction method. X-ray diffraction analysis confirmed the rhombohedral perovskite-like structure with minor traces of the impurity phases Bi₂Fe₄O₉ and Bi₂₅FeO₄₀. The lattice parameters a and c, and the volume of the hexagonal unit cell were extracted from the X-ray diffraction data and found to increase as the V⁵⁺ content is increased. The average crystallite size was estimated to be in the range 380–415 Å. Fourier transform infrared spectroscopy confirmed the rhombohedral perovskite-like structure via the vibration bands of the octahedral FeO₆ group observed between 410 and 570 cm⁻¹. A differential scanning calorimeter was used to record the thermal scans which revealed that the compounds have undergone crystalline phase transitions at temperatures in the range 300–320°C. A 4.5% V ^+ 5 substitution has shifted the transition peak by 20°C. The magnetic hysteresis loops taken at room temperature with a vibrating sample magnetometer revealed the ordinary ferromagnetic behavior. The V⁵⁺ substitution enhanced the remanent magnetization, but the magnetic coercivity was found to fluctuate around an average value of about 1000 Oe. The compound Bi_0.9Sm_0.1Fe_0.955V_0.045O₃ exhibited the maximum remanent magnetization.

KEYWORDS:

• X-ray diffraction
• spectroscopy
• magnetization
• coercivity
• phase transition

Disclosure statement

No potential conflict of interest was reported by the author(s).