Lithium ion conductivity of Li5+xBaxLa3−xTa2O12 (x = 0–2) with garnet-related structure in dependence of the barium content

摘要: The stoichiometry range and lithium ion conductivity of Li5+xBaxLa3−xTa2O12 (x = 0, 0.25, 0.50, 1.00, 1.25, 1.50, 1.75, 2.00) with garnet-like structure were studied. powder X-ray diffraction data indicated that single phase oxides exist over the compositional 0 ≤ x 1.25; while for 1.5, 1.75 2.00, presence second in addition to major garnet like was observed. cubic lattice parameter increases increasing reaches a maximum at 1.25 then decreases slightly further increase Li5+xBaxLa3−xTa2O12. impedance plots samples obtained 33 °C minimum grain-boundary resistance (Rgb) contribution total (Rb + Rgb) 1.0. (bulk grain boundary) ionic barium content Scanning electron microscope investigations revealed Li6.25Ba1.25La1.75Ta2O12 is much more dense, grains are regular shape. Among investigated compounds, exhibits highest bulk 5.0 × 10−5 7.4 S/cm °C, respectively.