Phase formation and dielectric properties of lithium fluoride-doped (Na0.5Bi0.5)TiO3–(K0.5Na0.5)NbO3–BiFeO3 ceramics

Abstract

Single-phase ceramic samples in the morphotropic phase boundary region of the (1–y)[(1–x)(Na_0.5Bi_0.5)TiO₃ ∙ x(K_0.5Na_0.5)NbO₃] ∙ yBiFeO₃ system (х = 0.06, 0.08, 0.10; y = 0.025, 0.05, 0.075, 0.10) have been prepared by solid-state reactions, and the effect of LiF as a low-melting-point additive (5 wt %) on the phase formation process and the dielectric properties of the solid solutions has been studied. The addition of LiF has been shown to activate the phase formation process and lower the sintering temperature of ceramic samples. The modification of the ceramics with lithium fluoride slightly increases the unit-cell parameters of the solid solutions. The addition of LiF lowers their Curie temperature.