Lead-free ferroelectric ceramics based on the Na0.5Bi0.5TiO3 system, in solid solution with Pr3+ and La3+, are synthesized by the Pechini method at low temperature. The powders calcined at 700 °C are found to be below 200 nm in mean crystal size. The dielectric properties reveal a diffuse phase transition. In Na0.5Bi0.5TiO3 ceramics the rhombohedral to tetragonal transition temperature (TR–T) appears near 190 °C, and the Curie temperature (TC) at 280 °C. These transitions are shifted when Pr3+ and La3+ cations are introduced into the lattice. The ferroelectric properties are also affected, causing the remnant polarization and coercive field to diminish with the increase in La3+ content. In addition, the piezoelectric properties decrease in the same way with La3+ concentration. Finally, the red luminescence of Pr3+ is improved when lanthanum concentration is increased.
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