Structure, conduction mechanisms and multiferroic properties of (Sm, Cr) co-doped Bi_0.89Sm_0.11Fe_0.97Cr _0.03O₃-NiFe₂O₄ composition thin films

(Sm, Cr) co-doped Bi_0.89Sm_0.11Fe_0.97 Cr_0.03O₃ (BSFC)-NiFe₂O₄ (NFO) composition thin films were successfully prepared on FTO/glass (SnO ₂:F) substrates via a sol-gel method. The structure, surface morphology, leakage current, ferroelectricity and ferromagnetism of BSFC-NFO composition thin film have been investigated. X-ray diffraction analysis indicates that the thin film is polycrystalline and consisted of a rhombohedral perovskite (R3m space group) BiFeO₃ phase and a cubic (Fd-3m space group) inverse spinel NiFe₂O₄ phase. The BSFC-NFO composition thin film is promising in practical application because of its well saturated ferromagnetic (Ms = 19.45 emu/cm³) and ferroelectric (Pr = 39 μC/cm²) hysteresis loops with low order of leakage current density (J = 6.73 × 10^-6 A/cm², at an applied electric field of 100 kV/cm). Which suggest the ferroelectric and ferromagnetic properties can be improved by this composition thin film structure. Moreover, the various conduction mechanisms of BSFC-NFO composition thin film have also been studied.