Luminescence and electrical properties of Eu-modified Bi0.5Na0.5TiO3 multifunctional ceramics

The Eu³⁺-modified Bi_0.5Na_0.5TiO₃ (BNT) ceramics have been fabricated by the solid-state reaction method. The impact of Eu³⁺ doping on the structure, photoluminescence, and electrical properties has been studied by XRD, SEM, PL spectra, and LCR meter. X-ray diffraction analysis reveals that the crystal structure of the samples is well matched with the trigonal perovskite, and the optimal temperature of presintering is 880°C. The Eu³⁺-doped BNT ceramics show excellent red fluorescence at 614 nm corresponding to the ⁵D₀→⁷F₂ transition of Eu³⁺ under 466 nm excitation and relatively long fluorescence lifetime. The BNT-0.02Eu ceramic density is up to 5.68 g/cm³ and the relative density is up to 94.6% with sintering temperature 1075°C. The piezoelectric constant (d₃₃) of samples has been significantly improved up to 110 pC/N by Eu³⁺ doping. The BNT-0.03Eu ceramic presintered at 880°C and sintered at 1050°C has good dielectric properties and excellent luminescence properties. Eu³⁺-doped BNT ceramics make it potential applications for novel integrated electro-optical and multifunctional devices.