Effect of Nonmagnetic Ion Substitution on Multiferroic Properties of BiFeO3

BiFeO3 is a ferroelectric and antiferromagnetic material at room temperature. In contrast to the weak ferromagnetism anticipated below T-N = 640 K, it exhibits no macroscopic moment due to a cycloidal spin ordering. This study attempts to perturb the cycloidal spin ordering and improve the multiferroic properties by substitutions of Al and Sc at Fe site. The compounds BiFe1-xAlxO3 (0 <= x <= 0.3) and BiFe1-xScxO3 (0 <= x <= 0.2), synthesized at high pressures and temperatures, crystallize with perovskite structure in polar space group R3c. With increasing Al/Sc concentration, the compounds undergo marked changes in magnetic properties. While Al-substituted compounds were lossy and exhibited a Maxwell-Wagner effect, the Sc-substituted compounds exhibited ferroelectricity at room temperature.

Automated summary

The study aimed to perturb the cycloidal spin ordering and improve the multiferroic properties of BiFeO3 by substitutions of Al and Sc at the Fe site. The results showed that the compounds with Sc substitution exhibited ferroelectricity at room temperature.