Synthesis and dielectric properties in the lithium-ion conducting material La0.5Li0.5−xNaxTiO3

• Published in: Journal of alloys and compounds 2021-12, Vol.889, p.161556, Article 161556
• Main Authors: V’yunov, O.I., Plutenko, T.O., Fedorchuk, O.P., Belous, A.G., Lobko, Ye.V.
• Format: Article
• Language: English
• Subjects: Ceramic; Ceramics; Chemical synthesis; Dielectric loss; Dielectric properties; Electrical properties; Equivalent circuits; Frequency ranges; Grain size; High dielectric constant; Impedance spectroscopy; Lanthanum; Lithium ions; Permittivity; Perovskite; Sodium; Solid solutions; Titanates
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.161556

•La0.5Li0.5TiO3 with improved dielectric properties were produced using Na.•High permittivity (ε~4·104 at 1 Hz) was achieved.•The number of vacant sites is controlled by the amount of Na.•The grain bulk and boundary contribute to the electrical properties. [Display omitted] Ceramic samples of Na-doped lithium lanthanum titanates have been synthesized by solid-state reaction technique. Scanning electron microscopy has shown that the grain size of ceramics in La0.5Li0.5−xNaxTiO3 solid solutions decreases with an increase in sodium concentration. Complex impedance spectroscopy measurements demonstrate that the origin of the electrical properties in La0.5Li0.5−xNaxTiO3 can be attributed to equivalent circuit consist of 3 elements, when x=0–0.4 and 2 elements when x=0.5. The dielectric constant and dielectric loss of polycrystalline samples of La0.5Li0.5−xNaxTiO3 have been investigated over a large frequency range. It has been found that the largest permittivity value is can be observed in La0.5Li0.4Na0.1TiO3 ceramic.