Multiferroic Properties of Single‐Phase Bi 0.85 La 0.15 FeO 3 Lead‐Free Ceramics

Single‐phase and lead‐free Bi 0.85 La 0.15 FeO 3 multiferroic ceramics were prepared by a rapid liquid sintering method to study their crystal structure and multiferroic behaviors. Rietveld refinement of X‐ray diffraction data showed a pseudo‐cubic structure plus a small triclinic distortion. The absence of Fe 2+ ions suggested few oxygen vacancies. Large polarizations of 20.3 μC/cm 2 together with a piezoelectric d 33 coefficient of ∼27.7 pC/N were achieved. This ferroelectricity originates from the stereochemical activity of the A‐site Bi 3+ lone electron pair. The remnant magnetizations of 0.0744–0.227 emu/g of Bi 0.85 La 0.15 FeO 3 permitted by the canting angle of canted antiferromagnetic order was released as a result of the collapse of the space‐modulated spin structure of BiFeO 3 . The observed dielectric anomalies proved the magnetoelectric couplings between ferroelectric order and canted antiferromagnetic order.