Li033La056TiO3

Li033La056TiO3, more commonly written as Li0.33La0.56TiO3 or LLTO, is a lithium lanthanum titanate ceramic oxide with a perovskite-related structure. Its composition reflects partial occupancy of the A-site by Li+ and La3+ ions in the TiO3 framework, yielding a material that conducts lithium ions rather than electrons.

LLTO is notable for its relatively high lithium-ion conductivity among solid electrolytes. At room temperature, dense LLTO single crystals or carefully prepared ceramics can exhibit ionic conductivities on the order of 10^-3 S/cm, with activation energies in the range of about 0.25–0.35 eV. A common challenge is that grain boundaries in polycrystalline samples tend to introduce significant resistance, which can substantially lower the overall conductivity compared with single-crystal specimens.

Synthesis and processing of LLTO typically involve solid-state reactions from Li2CO3, La2O3, and TiO2, followed by high-temperature sintering (often around 1100–1200 C). Lithium loss during firing is a major concern, so Li-rich formulations and protective atmospheres are frequently employed to maintain the target stoichiometry. Doping with elements such as Nb, Ta, or Al can modify the structure and reduce grain-boundary resistance, helping to improve density, stability, and conductivity.

Applications of LLTO focus on solid-state batteries as an electrolyte material, including configurations with lithium metal anodes. While LLTO offers high bulk ionic conductivity, practical performance depends on controlling grain boundaries, Li retention during synthesis, and interfacial compatibility with electrodes.