Crystal structure, leakage conduction mechanism evolution and enhanced multiferroic properties in Y-doped BiFeO3 ceramics

Ceramics of pure phase Yttrium (Y) doped BiFeO 3 prepared by a solid-state sintering route were characterized by X-ray diffraction, Raman spectroscopy, magnetic and electrical measurements. The results and analysis show that Y substitution greatly reduces the leakage current and enhances the multiferroic properties of BiFeO 3. Leakage conduction mechanism is shown to change from space-charge-limited conduction type in pure BiFeO 3 to a Poole–Frenkel emission behavior in Bi 0.90 Y 0.10 FeO 3. A Fowler-Nordheim tunneling mechanism in Bi 0.95 Y 0.05 FeO 3 ceramic is also evidenced under high electric fields. At the same time, enhanced magnetic properties due to Y-doping are confirmed by temperature dependent magnetometry and supported by Raman spectroscopy. An unexpected and sharp switching behavior in the magnetization under low magnetic fields observed in Bi 0.90 Y 0.10 FeO 3 ceramic, together with its improved ferroelectric property, may trigger such system for promising magneto-electric applications.