Effect of sintering temperature on structural, electrical, and magnetic properties of Bi2Fe4O9 polycrystalline materials

In the present paper, the effect of sintering temperatures (500 0C to 800 0C) on structural, and multiferroic properties of double perovskite Bismuth Ferrite (Bi2Fe4O9) materials synthesized through co-precipitation method has been investigated. The Powder X-ray diffraction and Raman spectroscopic studies revealed the formation of Mullite type Bismuth Ferrite (Bi2Fe4O9) with orthorhombic (Pbam) structure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) investigations reveal the formation of cuboid shape nanoparticles closely packed to each other. The particle size increases with increasing the sintering temperature from 500 0C to 800 0C. The Transmission electron microscopic (TEM) technique employed in both imaging and diffraction modes also confirms the growth of cubic nanocrystals of Bismuth Ferrite (Bi2Fe4O9). The saturated polarization–field curves for all samples sintered at different temperatures indicate the improvement of ferroelectric properties. The magnetic properties of Bi2Fe4O9 were investigated through hysteresis loops. The unsaturated curve of the magnetic field-dependent magnetization (M−H) of the materials at room temperature exhibits anti-ferromagnetic behavior.