Powder samples of Li1+x+yScxYyTi2−x−y(PO4)3 (x = 0.15 to 0.3, y = 0.01 to 0.15) were synthesized by solid phase reaction. The structure of the compounds was determined by X-ray diffraction patterns from the powder. The compounds belong to the rhombohedral symmetry (space group R3¯c) with Z = 6 formula units in the lattice. Ceramic samples were sintered in air at temperature Ts = 1523K varying sintering time from 1 to 5h. The element compositions of ceramics were defined by X-ray photo-electron spectroscopy. The complex impedance, electric conductivity, dielectric permittivity of the ceramics at 106 to 1.2 x 109Hz and 300 to 600K were carried out. Two relaxation dispersions of the electric parameters were found for all compounds. The dispersions were caused by the ion transport in grains and grain boundaries of the ceramic samples. The values of the bulk, grain boundaries conductivities, their activation energies, and dielectric permittivity were dependent on stoichiometric parameters x, y and sintering conditions of the ceramics.

Synthesis, Structure and Electrical Properties of Li1+x+yScxYyTi2−x−y(PO4)3 (x = 0.15–0.3, y = 0.01–0.15) Ceramics. A.F.Orliukas, T.Šalkus, A.Dindune, Z.Kanepe, J.Ronis, A.Určinskas, E.Kazakevičius, A.Kežionis, V.Kazlauskienė, J.Miškinis: Solid State Ionics, 2008, 179[1-6], 159-63