Annealing Effect on the Ionic Conductivity of La0.67-xLi3xTiO3 Made by Double Mechanical Alloying Method
Journal of Materials Science and Engineering: B
Perovskite La 2/3-x Li 3x TiO 3 with x = 0.11 (called LLTO11) powders were prepared by double mechanical alloying method from TiO 2 (99.99%), Li 2 CO 3 , (99.99%) and La 2 O 3 (99.9%) powders, in ideal cation stoichiometry for La 2/3-x Li 3x TiO 3 . The obtained single phase of LLTO11 powder was isostatically pressed under a pressure of 450 MPa and annealed at a temperature ranging from 1,100 °C to 1,250 °C. Optimal morphology and grain structure for the ionic conductivity of the samples were
... the samples were achieved at annealing temperature of 1,200 °C. For this ceramic, the lithium ionic grains and grain-boundaries conductivities at room temperature possess a value of 1.5 × 10 -3 S/cm and 4.8 × 10 -5 S/cm, respectively. The improvement in the grain-boundaries conductivity was explained due to the decrease of the number of grains, included grain boundaries and the diminution of the pores in LLTO samples annealed at 1,200 °C. The obtained results suggest useful applications of La (2/3)-x Li 3x TiO 3 (x = 0.11) ceramics for the production of the solid state electrolytes, for high-temperature Li-ionic batteries, in particular.