Diffused phase transition of Ba1−xEuxTiO3 ceramics

By applying the sol-gel method, we fabricated Ba 1− x Eu x TiO 3 (BET) ceramics as a single peroveskite phase in the composition range of x = 0 ~ 0.20. The BET ceramics displayed a ferroelectric phase transition temperature that changed from 120 ◦C to 80 ◦C, and exhibited the coexistance of the tetragonal, and cubic structures as the Eu composition was increased. They also displayed anomalous dielectric behaviors related to structural relaxation in the temperature range from 200 ◦C to 600 ◦C. We considered the Arrhenius temperature dependence of the dielectric relaxation time by using the electric modulus formalism. The characteristic activation energy was thought to be related with the substitution of Eu (Eu 2+ , Eu 3+ ) ions for Ba 2+ or Ti 4+ ions in the perovskite structure.