Photoluminescence, Structural, and Electrical Properties of Erbium‐Doped Na_0.5Bi_4.5Ti₄O₁₅ Ferroelectric Ceramics

Abstract

Structural, electrical, and up-conversion (UC) properties of Na 0.5 Bi 4.5-x Er x Ti 4 O 15 (NBT-xEr 3+ ) (0.00 < x < 0.40) ceramics have been studied. All the ceramic samples possessed a single-phase orthorhombic structure. The unit cell volume, the lattice parameters a, b, and c, and orthorhombic distortion analyzed on the basis of Rietveld refinement were observed to decrease with increasing Er 3+ contents (x). The average values of grain size were found to slightly decrease with increasing x. Raman spectroscopy revealed that (Bi 2 O 2 ) 2+ layers remained unaffected in the modified compositions, and Er 3+ substitution for Bi 3+ occurred predominantly at the A-site in the perovskite blocks causing the cationic disorder and a slight decrease in the TiO 6 octahedral distortion. NBT-xEr 3+ ceramic with x = 0.20 achieved the optimized photoluminescence. The relative intensity of green and red UC emissions could be tuned by changing Er 3+ ions concentrations. Ferroelectric measurements revealed that Er 3+ doping led to reduction in 2P r and 2E c . However, dielectric measurements showed that the incorporation of Er 3+ ions increased T c with simultaneously lowered tand at high temperature, implying that this ceramics can be suitable for high-temperature sensor applications.

Tunable Luminescence Contrast of Na0.5Bi4.5Ti4O15:Re (Re = Sm, Pr, Er) Photochromics by Controlling the Excitation Energy of Luminescent Centers

“…For the purpose of photoswitching luminescence with high contrast, this possible utilization of excitation wavelengths at lower energy is usually less destructive to both information recording and the recording material itself during luminescent readout processes. 20,21 The strongest diffraction peak is found to be the (119) orientation, aligning with the fact that the most intense reflections of bismuth layer structures are the (112m + 1). Compared with pure Na 0.5 Bi 4.5 Ti 4 O 15 , rare earth doping induces the shift of diffraction peaks to higher angles, clearly observed in the Sm-doped sample.…”

“…XRD analyses of rare earth-doped Na 0.5 Bi 4.5 Ti 4 O 15 samples (Na 0.5 Bi 4.5 Ti 4 O 15 :Re = Sm, Pr, and Er) reveal only a single-phase bismuth layer-type structure with m = 4 within the composition studied here, as shown in Figure S1. These diffraction peaks can be well indexed by a standard PDF card of Na 0.5 Bi 4.5 Ti 4 O 15 (PDF#01-074-1317), similar to results reported in the literature. , The strongest diffraction peak is found to be the (119) orientation, aligning with the fact that the most intense reflections of bismuth layer structures are the (112 m + 1). Compared with pure Na 0.5 Bi 4.5 Ti 4 O 15 , rare earth doping induces the shift of diffraction peaks to higher angles, clearly observed in the Sm-doped sample.…”

“…Ten major bands, centered at ∼68, 83, 108, 145, 229, 270, 341, 494, 543, and 572 cm –1 , are observed and labeled ν 1 to ν 10 , respectively, for all samples. As shown in ref − the phonon modes below 200 cm –1 (ν 1 , ν 2 , ν 3 , and ν 4 ) originate from the vibrations of A-site ions in the pseudoperovskite layer. The modes at high frequency are generally believed to come from the vibrations of TiO 6 octahedra, while the modes of ν 6 and ν 9 (or ν 10 ) are attributed to the torsional bending vibrations and stretching vibrations, assigned to the F 2g and E g (splitting into B 2g and B 3g modes) characters, respectively.…”

Topochemical synthesis and structural characteristics of orientation-controlled (Bi0.5Na0.5)0.94Ba0.06TiO3 perovskite microplatelets

“…These platelets were ~6.1-10.5 μm in length and ~0.9-2.0 μm in thickness. The microstructure/crystallinity damage caused by the structural conversion was completely healed at this stage, which occurred through secondary recrystallization or Ostwald ripening [30] . To be specific, the polycrystalline aggregates sintered and recrystallized into the single crystals.…”

Enhanced piezoelectric performance in Na0.5Bi4.5Ti4O15‐based bismuth‐layered ceramics by Nb/Mn doping modification

“…(B) The relationship of d 33 , lattice constant b/a, and the Curie temperature with different Nb 5+ contents. (C) The temperature-dependent d 33 of Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics in the temperature range of 25 • C-450 • C. (D) The piezoelectric performance of Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics compared with other high-T c piezoelectric ceramicsbismuth layer piezoelectric ceramic materials, which have great potential application prospects in extremely harsh high-temperature environments 2,24,34,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55]. In summary, Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics were prepared by the conventional solid-state method.…”