Structure, Ferroelectric and Photoluminescence Properties of Eu-Doped CaBi4Ti4O15 Multifunctional Ceramics

Abstract

Lead-free multifunctional ceramics of CaBi 4Àx Eu x Ti 4 O 15 were prepared by a traditional solid state method, and the effects of Eu doping on structure, ferroelectric, piezoelectric and photoluminescence properties of the ceramics were investigated. All the ceramics possessed typical bismuth layer structure with m = 4, belonging to orthorhombic symmetry, and no secondary phase was detected. The plate-like grains were observed in all the ceramics, and the grain growth was slightly inhibited after the addition of Eu. Saturated polarization hysteresis loops were observed for all the ceramics, and the remanent polarization P r decreased with Eu doping. The Eu-doped ceramics had a sharp excitation band centered at 465 nm due to the f-f transition from the 7 F 0 ground state to the 5 D 2 excited state of Eu 3+ . Under the excitation by 465 nm light, the main emission peaks located at 595 nm and 616 nm were obtained, which corresponds to the transition of 5 D 0 -7 F 1 , 5D 0 -7 F 2 levels in Eu 3+ , respectively. Our study shows that CaBi 4 Ti 4 O 15 ceramics may be a promising multifunctional material for potential applications in optical-electro integration devices.

Exploration of structural, vibrational and spectroscopic properties of self-activated orthorhombic double molybdate RbEu(MoO4)2 with isolated MoO4 units

“…In modern photonics, the crystals containing europium ions are of particular interest because of the efficient red emission provided by Eu 3+ ions under the short-wavelength excitation and this property is extremely needed for the WLED devices and other optical systems [1][2][3][4][5]. By now, a lot of different Eu 3+ -doped phosphors with a complex structure have been proposed and their spectroscopic properties have been evaluated [6][7][8][9][10][11][12]. However, in the solid solutions, the Eu 3+ doping level is commonly low to avoid the concentration-quenching effects and, respectively, the crystallographic positions of Eu 3+ ions may be not evident.…”

Enhanced ferroelectricity/piezoelectricity, bright blue/yellow emission and excellent thermal stability in Ca1−x(LiDy)x/2Bi4Ti4O15 lead-free multifunctional ceramics

“…[14][15][16] As typical materials with fourth-layer bismuth layer structure, CaBi 4 Ti 4 O 15 (CBT) possesses high Curie temperature of 790 C and has been considered as one of promising multifunctional materials. For instances, Er/Eu/Hodoped CBT ceramics [17][18][19] have been reported and the materials show excellent ferroelectric/piezoelectric properties and luminescence. However, to our knowledge, there is no report on rare earth elements Dy-doped CBT ceramics.…”

Improved ferroelectric/piezoelectric properties and bright green/UC red emission in (Li,Ho)-doped CaBi4Ti4O15 multifunctional ceramics with excellent temperature stability and superior water-resistance performance

“…have been developed. Among these BLSF materials, CaBi 4 Ti 4 O 15 (CBT) is considered as a promising candidate for high-temperature piezoelectric materials, belongs to a typical bismuth layer structure with m = 4 and possesses a high Curie temperature (∼790 °C), good resistivity and relatively strong piezoelectricity (d 33 = 7.0 pC N −1 29 However, to our knowledge, there is no report on Ho-doped CBT ceramics. It has been known that Ho 3+ is a crucial activator ion and Hocontaining materials show excellent green emission and red up-conversion emission due to the transition of the 5 S 2 → 5 I 8 and 5 F 5 → 5 I 8 levels of Ho 3+ ions, respectively.…”