Insights into the dielectric and luminescent properties of Na0.5Pr0.003Bi0.497−xLaxTiO3 synthesized by the Pechini method

Abstract

Lead-free ferroelectric ceramics based on the Na(0.5)Bi(0.5)TiO3 system, in solid solution with Pr(3+) and La(3+), 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 Na(0.5)Bi(0.5)TiO3 ceramics the rhombohedral to tetragonal transition temperature (T(R-T)) appears near 190 °C, and the Curie temperature (T(C)) at 280 °C. These transitions are shifted when Pr(3+) and La(3+) 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 La(3+) content. In addition, the piezoelectric properties decrease in the same way with La(3+) concentration. Finally, the red luminescence of Pr(3+) is improved when lanthanum concentration is increased.

A highly efficient, orange light-emitting (K0.5Na0.5)NbO3:Sm3+/Zr4+lead-free piezoelectric material with superior water resistance behavior

“…It can be seen that the samples doped with Zr 4+ ions show high PL QYs ranging from 0.40 to 0.53. Especially, the sample with 0.010 mol Zr 4+ exhibits the best result, the QY value reaches 0.53, which is superior to the recently reported QY values of RE-doped ferro-/piezoelectric materials, 17,18,21,23,47 and comparable to some commercial phosphors, such as Y 2 O 2 S/Y 2 O 3 :Eu 3+ . 48 Since the QY is closely correlated with the microstructure, processing conditions, the particle/grain size, and the crystallinity of materials, the higher QYs can be obtained by further optimization of the KNSNZ x system.…”

“…These experiments show that the simultaneous existence of luminescence and ferro-/piezoelectric properties may be realized by controlling the host and rare earth-ion dopants. 21,22 For example, in the Pr 3+ -doped KNN host, a dual-enhancement of both the ferro-/piezoelectric and the photoluminescence performance can be realized. 23 Unfortunately, low luminescence efficiency in RE-doped ferro-/piezoelectric oxides is still a difficult problem that some researchers face due to their larger phonon energies.…”

(K0.5Na0.5)NbO3:Eu3+/Bi3+: a novel, highly efficient, red light-emitting material with superior water resistance behavior

“…Recently, several studies on RE-doped ferroelectric oxides have been published. [12][13][14][15][16] The simultaneous existence of luminescence and ferroelectric/piezoelectric properties has been realized, as well as a dual-enhancement of both the ferro-/ piezoelectric and the photoluminescence performance in Pr 3+ doped KNN ceramics. 17 These results indicate that RE-doped ferroelectric oxides may see a potential application in novel multifunctional devices by integrating at least two characteristics.…”

Investigation of structural and optical spectroscopy of 5 % Pr doped (Bi0.5Na0.5) TiO3 ferroelectric ceramics: site depended study

“…There are two possible reasons for the red shift (1) local structure change due to the dopant [31,37] and (2) impurity/Oxygen vacancies [38]. According, to Niranjan et al [26], there is a weak hybridization between O-2p orbitals and Bi-6p at lower energy part of the VBs as well as the Ti- [39], obtained the covalent of Pb-O bonding, which strongly affects O 2p-Ti 3d hybridization in the TiO 6 octahedron.…”