Photoluminescence and electrical characterization of unfilled tetragonal tungsten bronze Ba4La1 − xEuxTiNb9O30

• Unfilled TTB structure BLTN: Eu3+x ceramics have been synthesized.
• Photoluminescenct properties of the BLTN: Eu3+x ceramics have been first reported.
• Bright red emission excited by NUV light has been observed at room temperature.
• Obvious variations of dielectric characteristics have been confirmed.
• Relaxor-like ferroelectric phase transitions have been detected.

Unfilled tetragonal tungsten bronze (TTB) structure Ba4LaTiNb9O30 doped by Eu3+ (BLTN: Eu3+x) with different x have been prepared, and their structural, photoluminescence, dielectric, and ferroelectric properties are carefully investigated in this work. Bright red emission, originating from 5D0 → 7F1 and 5D0 → 7F2 transitions of Eu3+ ions, has been observed by naked eyes at room temperature under near ultraviolet (NUV) light excitation. Optimized emission intensity is obtained when x = 1.00 for present unfilled TTB-type BLTN: Eu3+x samples. Furthermore, with increasing x, the dielectric and ferroelectric characteristics of the unfilled TTB-type BLTN: Eu3+x samples also display remarkable variation. When x ≥ 0.50 relaxor-like ferroelectric phase transitions are detected above room temperature, it is believed that unfilled TTB-type BLTN: Eu3+x = 1.00 involving bright photoluminescence and enhanced ferroelectric properties may act as a potentially multifunctional optical-electro material.

PL spectra of the unfilled TTB structure BLTN: Eu3+x samples (x = 0.00, 0.25, 0.50, 0.75, and 1.00) excited by 399 nm. The inset is a schematic diagram of the unfilled TTB structure.Figure optionsDownload as PowerPoint slide