Oxygen octahedra distortion‐induced multiferroic properties of Er and Zr co‐doped BiFeO ₃ 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 ( R 3 c ). 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.