Anomalous phase transitions of lead-free piezoelectric xNa 0.5 Bi 0.5 TiO 3 -(1-x)BaTiO 3 solid solutions with enhanced phase transition temperatures

摘要: Temperature-dependent structural phase transitions and dielectric properties for a series of xNa(0.5)Bi(0.5)TiO(3)-(1-x)BaTiO(3) (NBT-BT) samples where x ranges from 0.05 to 0.30 have been investigated. Non-ambient x-ray diffraction together with data as function temperature demonstrated an enhancement in the ferroelectric paraelectric transition increase NBT content, including inhibition two well-known low-temperature polymorphic BaTiO(3). Anomalous response has observed >= 0.20 suggesting crossover first-order second-order transition. The critical point lies between x=0.15 x=0.20. Deviation classical Curie-Weiss law seen having 0.10. A modified was employed model maximum value exponent gamma found be 1.45 x=0.30. It is suggested that are heavily influenced by induced strain upon doping rather than chemical inhomogeneities disorder, which common occurrences doped ferroelectrics.