Phase transition, structural and magnetic parameters of vanadium-substituted Bi0.9Sm0.1FeO3 multiferroic ceramics.

The inorganic multiferroic compounds Bi0.9Sm0.1Fe1 − xVxO3 (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 Bi0.9Sm0.1Fe0.955V0.045O3 exhibited the maximum remanent magnetization. [ABSTRACT FROM AUTHOR]