Structural, optical and electromagnetic properties of Bi1−xHoxFeO3 multiferroic materials

Bi1−xHoxFeO3 (x = 0.00, 0.05, 0.10, 0.15 and 0.20) polycrystalline ceramics were synthesized by a solid-state reaction and their structural, absorption, Raman scattering, impedance and magnetic properties were investigated. The substitution of rare earth Ho for Bi was found to decrease the impurity phase in BiFeO3 ceramics. There appears an anomalous change in the lattice constants, optical band gap as well as the impedance spectroscopy and magnetization of samples at x = 0.10, suggesting a limit of dissolubility of Ho doped ions in BiFeO3. Additionally, the Raman measurement performed for the lattice dynamics study of Bi1−xHoxFeO3 samples reveals a band centered at around 1000–1300 cm−1 which is associated with the resonant enhancement of two-phonon Raman scattering in the multiferroic Bi1−xHoxFeO3 samples. Ho-doped BiFeO3 also showed a ferromagnetic-like behavior with Mr = 1070 × 10−4 and Ms = 1.60 emu/g for optimum content x = 0.10, which is similar to the solid solution system of BiFeO3.

Research highlights▶ The result also suggests the limit of dissolubility of Ho doped ions in BiFeO3. The Ho dopant in the limit of dissolubility has improved the magnetization of BiFeO3 compound.