Structural and dielectric studies of relaxor ferroelectric Ba1-xLax(1-y)/2Euxy/2TiO3 ceramics
Résumé
Structural and dielectric properties of Ba1−xLax(1−y)/2Euxy/2Nax/2TiO3 (0 ≤ x ≤ 0.5) have been investigated. Ceramic samples were elaborated by the classical solid-state routine, they crystallize in the tetragonal distorted perovskite structure for 0 ≤ x ≤ 0.1 and in cubic for 0.1 ≤ x ≤ 0.5. Dielectric measurements showed that the compounds exhibit an evolution from a classical ferroelectric to a relaxor ferroelectric with rising substitution rate x. TC or Tm and ε′r decrease when x increases. This study is in the field of preparation of lead-free relaxor ceramics, which have a great importance for the environment.