Growth and investigation of lithium-substituted perovskite-type ionic conductor

Ivanov-Schitz, A. K.; Kireev, V. V.; Chaban, N. G.

doi:10.1016/s0167-2738(00)00476-8

Cited by 9 publications

(3 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Structural modifications are expected by introducing alkaline ions, which replace some proportions of lanthanum ones to preserve the crystal electroneutrality, in the vacant A-sites giving rise to the series La 1.33 - x A 3 x Ti 2 O 6 . These compounds are of interest because they exhibit ionic conductivity (A = Li) and dielectric (A = Na) properties; both structural and electrical properties have been extensively investigated. − Similarly to the previous systems, different structural models have been proposed for these derivatives depending on the nature of A-cation, vacancies number, composition, and syntheses conditions.…”

Section: Introductionmentioning

confidence: 99%

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study

et al. 2005

View full text Add to dashboard Cite

Polycrystalline samples of general composition La1.33 - x Na3 x Ti2O6 were prepared by the “liquid mix” technique. The structural analysis carried out from different techniques (XRPD, ED, HREM, and NPD) evidences that these perovskites undergo phase transformations that seem to be mainly related to the number of A-vacancies. For high degrees of substitution, x, that imply low number of vacant A-sites, a random distribution of Na+ and La3+ ions in these sites is observed. When this number increases (for x = 0.16 and 0.11) two different cells are adopted, in which the A-cations are ordered by layers along one direction, whose dimensions are a ≈ b ≈ √2a p; c ≈ 2a p (space group Pbmm) and a ≈ b ≈ c ≈ 2a p (space group Cmmm), respectively. These structural changes are analyzed on the basis of the group−subgroup relations and the tilting of the TiO6 octahedra.

show abstract

Section: Introductionmentioning

confidence: 99%

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study

et al. 2005

View full text Add to dashboard Cite

show abstract

“…On the other hand, the cause of non-Arrhenius behavior remains under debate. The Vogel–Tamman–Fulcher (VTF) equation, which is similar to that for supercooled liquids, has also been used to explain this phenomenon. ,, However, the experimental results show the two-step thermal activation process rather than the VTF behavior. Therefore, we concluded that the non-Arrhenius behavior is due to changes in the local structure of LLTO.…”

Section: Resultsmentioning

confidence: 99%

Lithium-Ion Diffusion in Perovskite-Type Solid Electrolyte Lithium Lanthanum Titanate Revealed by Pulsed-Field Gradient Nuclear Magnetic Resonance

et al. 2023

View full text Add to dashboard Cite

Pulsed-field gradient nuclear magnetic resonance (PFG-NMR) is a powerful tool for measuring the diffusion coefficient of lithium in solid electrolytes. In this study, the temperature dependence of the lithium diffusion coefficient in polycrystalline Li 0.29 La 0.57 TiO 3 (LLTO) is determined by carefully designed experiments. The microstructure of LLTO consists of randomly oriented grains and 90°d omains. The echo decay of the PFG is not linear, as predicted by the Stejskal−Tanner equation, but is curvilinear. The decay curves are analyzed with theoretical equations for randomly oriented crystals to provide evidence of two-dimensional diffusion of Li + ions in LLTO. The NMR and conductivity diffusion coefficients agree well with each other over a wide temperature range of 273−723 K and exhibit non-Arrhenius behavior. Since the timescale of the PFG-NMR diffusion coefficient corresponds to the bulk ionic conductivity, the origin of non-Arrhenius behavior is not the number of carriers but rather the change in the mobility of Li + ions in LLTO. Specifically, the activation energy of local Li + -ion hopping decreases at temperatures above 450 K. Herein, the results are discussed in comparison with other experimental data and molecular dynamics simulations.

show abstract

“…However, the lithium loss during the synthesis of precursor materials and/or in the crystal growth process constitutes a drawback . Additionally, the growth of LLTO single crystals from the melt is scarcely documented in the literature, and the existing articles report that the original composition deviates from the initial stoichiometry, which favors the raise of secondary phases in the microstructure. − Moreover, the behavior of LLTO formation at temperatures higher than 1100 °C is still a controversial matter in the literature. − …”

mentioning

confidence: 99%

Innovative Design for the Enhancement of Lithium Lanthanum Titanate Electrolytes

Oliveira

Andreeta

Souza

et al. 2019

Crystal Growth & Design

View full text Add to dashboard Cite

The high ionic conductivity in lithium lanthanum titanate perovskite ceramics, Li3x La(2/3)‑x TiO3 (LLTO), is well-known for the x ≈ 0.11 lithium concentration. The grain conductivity is approximately 10–3 S·cm–1 at room temperature, which makes this compound one of the best candidates for the development of solid-state electrolytes. However, lower grain boundary conductivity (10–6 to 10–4 S·cm–1) blocks lithium diffusion. In order to increase the total conductivity of LLTO ceramics, single crystal fibers of lanthanum aluminate (LAO) were inserted into its green ceramic matrix. Our hypothesis is that single crystal fibers are capable of inducting LLTO abnormal grain growth, thus improving the overall electrical conductivity of the composite. The results show that LAO single crystals act like seeds, creating abnormal grain growth at the LaAlO3 fiber surface. The impedance spectroscopy shows that the new composites have a substantial relative enhancement of total ionic conductivity (more than 200%) in comparison with the monolithic ceramic samples. This result shows the possibility of developing a novel composite design as a candidate for solid electrolyte applications.

show abstract

Growth and investigation of lithium-substituted perovskite-type ionic conductor

Cited by 9 publications

References 12 publications

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study

Lithium-Ion Diffusion in Perovskite-Type Solid Electrolyte Lithium Lanthanum Titanate Revealed by Pulsed-Field Gradient Nuclear Magnetic Resonance

Innovative Design for the Enhancement of Lithium Lanthanum Titanate Electrolytes

Contact Info

Product

Resources

About

Growth and investigation of lithium-substituted perovskite-type ionic conductor

Cited by 9 publications

References 12 publications

Structural Modifications Induced by Composition in the La1.33-xNa3xTi2O6 Perovskites: A Neutron Diffraction Study

Structural Modifications Induced by Composition in the La1.33-xNa3xTi2O6 Perovskites: A Neutron Diffraction Study

Lithium-Ion Diffusion in Perovskite-Type Solid Electrolyte Lithium Lanthanum Titanate Revealed by Pulsed-Field Gradient Nuclear Magnetic Resonance

Innovative Design for the Enhancement of Lithium Lanthanum Titanate Electrolytes

Contact Info

Product

Resources

About

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study

Structural Modifications Induced by Composition in the La_1.33_-_xNa₃_xTi₂O₆ Perovskites: A Neutron Diffraction Study