Structural and multiferroic properties of Nd and Mn co-doped 0.55BiFeMnO3-0.45BaTiO3 ceramics with high energy storage efficiency

(1-x) BiFeO3-xBaTiO3 bulk composite ceramics are appealing for storage devices owing to its prominent ferroelectric properties and Pb-free characteristics. However, it is desirable to further improve their energy storage efficiency and ferromagnetic properties. In this work, the effect of Nd doping concentration on the structural, multiferroic properties of Bi0.55-xNdxFe0.54Mn0.01O3-(BaTiO3)0.45 have been investigated. When the Nd content increased from 0.05 to 0.15, SEM characterization showed that the average grain size decreases, and the saturated polarization (Ps) decreases from 32.68 to 14.49 mu C/cm2 under the electric field of 100 kV/cm; however, the breakdown electric filed strength improved from 100 to 150 kV/cm. The energy storage efficiency as high as 86.4% and an energy density of 1.46 J/cm3 were achieved under the electric field of 150 kV/cm for x = 0.15. In addition, the ferromagnetic properties are clearly observed in the Nd and Mn co-doped 0.55BiFeO3-0.45BaTiO3 composite ceramics, while a hysteresis loop was not detected in the undoped sample fabricated under the same conditions. A maximum remnant magnetization (Mr) of 0.126 emu/g was obtained at x = 0.15.