Ferroelectric properties of magnetoelectric CoFe2O4/Bi3.15Nd0.85Ti3O12 composite ceramics with coherent-lattice interfaces.

The CoFe 2 O 4 (CFO)/Bi 3.15 Nd 0.85 Ti 3 O 12 (BNdT) composite ceramics with coherent-lattice interfaces were prepared to keep good ferroelectricity. The coherent-lattice interfaces exhibit (020) BNdT //(130) CFO orientation, as a result of a very small lattice mismatch. Raman spectra indicate symmetry breaking of CFO phase with the forbidden A 1g mode (~ 684 cm − 1 ) leading to new modes around 727 and 734 cm − 1 , suggesting that coherent interfaces have superlattice-like characteristics. The electric breakdown field increases to 400 kV/cm for the 30 mol% CFO ceramic comparing with 250 kV/cm for the pure BNdT. Partly enhanced ferroelectric polarization, as measured by hysteresis loops, is observed likely helped by this superlattice-like bonding. [ABSTRACT FROM AUTHOR]