Structure, dielectric, ferroelectric, and magnetic properties of (1 − x) BiFeO3–x (Ba0.85Ca0.15)(Zr0.10Ti0.90)O3 ceramics

• BFO–BCZT ceramics transformed from rhombohedral to pseudocubic with increasing x.
• The electrically heterogeneous microstructure is caused by the IBLC effects.
• The optimal ferroelectric and magnetic properties were obtained at 0.30 ≤ x ≤ 0.35.

Polycrystalline (1 − x) BiFeO3–x (Ba0.85Ca0.15)(Zr0.10Ti0.90)O3 [(1 − x) BFO − x BCZT)] ceramics were fabricated by a solid state reaction method. The phase structure, microstructure, and dielectric, ferroelectric and magnetic properties of the (1 − x) BFO − x BCZT ceramics were systematically investigated. The crystal structure of the (1 − x) BFO − x BCZT ceramics transformed from rhombohedral to pseudocubic with increasing x. A morphotropic phase boundary existed at the composition of 0.20 ≤ x ≤ 0.30. The average grain size of the ceramics initially increased to a maximum at x = 0.30 and then decreased. The frequency dependence of dielectric constant and complex impedance plots indicated an electrically heterogeneous microstructure for x ≤ 0.20 caused by the coexistence of Fe2+ and Fe3+. Tm and ϵm decreased with increasing x for 0.25 ≤ x ≤ 0.80, and the hysteresis loops (P–E) became slimmer with increasing x. All samples presented weak ferromagnetic ordering, indicating that the substitution of BCZT into the BFO matrix released its potential magnetization. The optimal ferroelectric and magnetic properties, Pr of 22.7–27.3 μC/cm2 and Mr of 0.0394–0.0744 emu/g, were obtained at 0.30 ≤ x ≤ 0.35.

Figure optionsDownload as PowerPoint slide