Oxygen octahedra distortion‐induced multiferroic properties of Er and Zr co‐doped BiFeO₃ nanoparticles

Abstract

The present work unveiled the distortion of oxygen octahedra influencing magnetic and magnetoelectric properties of novel Bi 1−x Er x Fe 1−y Zr y O 3 (x = 0, .05, .1, y = .02, .05) polycrystalline nanoparticles by sol-gel route. X-ray diffraction patterns analysis reveals that pristine BiFeO 3 and doped BiFeO 3 are crystalized in the rhombohedral structure (R3c). The Fe-O-Fe bond angle of Bi 1−x Er x Fe 1−y Zr y O 3 (x = 0, .05, .1, y = .02, .05) varies between 141 • and 159.62 • as the concentration of Er (via Bi site) and Zr (via Fe site) ions increases in BiFeO 3 . As a result, the tilt angle of oxygen octahedra and the canting angle of spiral spin arrangement increase. Hence, the maximum magnetization varies between .03144 and .37558 emu/g in Er and Zr co-doped BiFeO 3 system. The number of electrons per unit cell of Bi 1−x Er x Fe 1−y Zr y O 3 (x = 0, .05, .1, y = .02, .05) lies between 733.38 and 831, respectively. Further, the number of coherently diffracting domains increases from 3.07 to 5.21, and then it decreases when Er and Zr are increased in BiFeO 3 . Consequently, the magnetoelectric coupling coefficient varies between .0265 and .2511 mV/cm Oe, respectively. Particularly, Bi 0.95 Er 0.05 Fe 0.98 Zr 0.02 O 3 shows enhanced magnetic and magnetoelectric behaviors compared to other samples.