Multifunctionality of rare earth doped 0.925Na(0.5)Bi(0.5)TiO(30.075)K(0.5)Na(0.5)NbO(3) ferroelectric ceramics
Résumé
Undoped and RE3+ (RE: Pr; Nd; Dy; Ho; Tm) doped 0.925Na(0.5)Bi(0.5)TiO(3)-0.075K(0.5)Na(0.5)NbO(3) (NBTKN0.075/ NBTKN0.075-RE) ceramics were synthesized using the solid-state synthesis method. X-ray diffraction analysis revealed a pure perovskite structure without secondary phases. The Ho, Dy and Tm ions revealed a dielectric curve with a more diffused phase transition associated with a high value of the dielectric constant, while the lowest diffusivities were found for the Nd and Pr ions doped NBTKN0.075. The ferroelectric hysteresis loops show the significant increase of polarization and electric breakdown strengths (BDS) in all doped samples, accompanied by P-E shape changes under the influence of the different RE3+ ions. In the optical studies, the conversion of near-infrared light to visible light was investigated for Ho3+ and Dy3+ doped NBTKN0.075. The sample with Ho3+ produced a strong green-yellow up-conversion (UC) emission. At an excitation of lambda ex = 800 nm, the blue-green UC emission of the Dy ion showed that the UC is due to the energy transfer interaction. CIE diagram with the corresponding (x, y) coordinates were used to clearly identify the overall color of the multichromatic spectral emissions in each spectrum. The additional functionality of up-conversion emission in the ferroelectric NBTKN0.075-RE material, and its positive ef-fects on the electrical proprieties, open the possibility to realize multifunctionality in a wide range of ap-plications.(c) 2022 Elsevier B.V. All rights reserved.