New Antiferroelectric Solid Solution of Pb ( Mg _1/2 W _1/2 ) O ₃ – Pb ( Zn _1/2 W _1/2 ) O ₃ as Dielectric Ceramics

Abstract

A new solid solution of (1− x ) Pb ( Mg 1/2 W 1/2 ) O 3 – x Pb ( Zn 1/2 W 1/2 )O 3 has been prepared in the form of ceramics by solid‐state reaction with composition x up to 30%. It is found that with the substitution of Zn 2+ for Mg 2+ on the B site of the of complex perovskite structure the antiferroelectric (AFE) Curie temperature T C of PMW increases from 40°C ( x = 0) to 67°C ( x = 30%), indicating an enhancement of antiferroelectric order, whereas, at the same time, the phase transition becomes more diffuse due to a higher degree of chemical inhomogeneity. X‐ray diffraction analysis indicates that the crystal structure adopts an orthorhombic space group ( Pmcn ) with a decrease in lattice parameter a, but an increase in b and c as the Zn 2+ concentration increases. The low dielectric constant (~ 10 2 ), low dielectric loss (tanδ ≈ 10 −3 ), linear‐field‐induced polarization, and significantly high breakdown field (~ 125 kV/cm) at room temperature make this family of dielectric materials a promising candidate for ceramic insulators.