Synthesys and Electrical Properties of Li1+xZr2-2xAlxTix(PO4)3 Superionic Ceramics

Abstract

The compounds of the system Li1+xZr2-2xTixAlx(PO4)3 (where x = 0.1 – 0.3) were synthesized by a solid state reaction. The chemical composition and structure of the powder were studied by chemical analysis and X-ray diffraction. The ceramic samples were sintered and their electrical properties were investigated by complex impedance spectroscopy in the frequency range 1.0×106 Hz – 1.2×109 Hz and temperature range 300 – 600 K. Two relaxation dispersions related to the fast Li+ ion transport in bulk and grain boundaries were found. The activation energy of the temperature dependent conductivity and relaxation frequency in bulk were obtained from the slops of Arrhenius plots. The values of the activation energy related to the bulk ionic conductivity and relaxation frequency in bulk were found to be very similar in each of the investigated materials. That can be attributed to the fact that the temperature dependences of bulk conductivity are caused only by the mobility of the fast Li+ ions, while a number of charge carriers remains constant with temperature.