Mg-substitution for promoting magnetic and ferroelectric properties of BiFeO₃ multiferroic nanoparticles

Mg-substituted BiFeO₃ (BFO) multiferroic nanoparticles were synthesized by a facile sol-gel route and their magnetic and ferroelectric properties were investigated. Due to Mg²⁺ ion substitution, the magnetization is dramatically increased and higher than the other A-site substituted BFO reported with similar doping level. Such strong magnetization improvement originates from the release of latent magnetization locked within the cycloid, which is caused by the substitution of small-radius Mg²⁺ ion at the edge of the perovskite-structure tolerance factor. Compared to the pristine BFO, the as-doped Bi_0.98Mg_0.02FeO₃ exhibits five-fold improved magnetization with simultaneously improved ferroelectric properties at room temperature. Increased magnetic and ferroelectric properties suggest the doped BFO possesses great potential for data storage and magnetoelectric devices.