Structure and properties of (1 − x)BiFeO3 · xPbFe2/3W1/3O3 (0 ≤ x ≤ 1) solid solutions

(1 − x )BiFeO 3 · x PbFe 2/3 W 1/3 O 3 ((1 − x )BFO · x PFWO) samples with 0 ≤ x ≤ 1 have been prepared by a standard ceramic processing technique and characterized by X-ray diffraction, dielectric measurements, and Mössbauer spectroscopy. The system has been shown to contain a continuous series of perovskite solid solutions. The solid solutions in the range 0 ≤ x < 0.32 have a rhombohedral structure and those with 0.32 ≤ x ≤ 1 have a cubic structure. Increasing the BFO content from 0 to 40% leads to rapid degradation of the dielectric permittivity peak that occurs at 180 K in PFWO and is due to the relaxor behavior of this component. At higher BFO concentrations, the electrical conductivity of the solid solutions increases by about two orders of magnitude. The temperature dependences of permittivity for the samples containing ∼80% BFO have prominent maxima around 430 and 520 K, whose position is frequency-independent. The solid solutions exhibited no piezoelectric or pyroelectric effect, probably because they were insufficiently poled in a field of 10 kV/cm at 300 K. At higher electric field intensities, the samples experienced breakdown.