Superionic transitions in NASICON-type solid electrolytes

Four different methods, temperature dependent X-ray diffraction, impedance measurements, calorimetry and dilatometry, were employed to investigate the superionic transitons of NASICON type materials. Two singularities are found at 160 – 170 °C and about 230 °C. The first one is related to a second order phase transition close to the temperature of structural phase transition; the second one coincides with the inflection in the temperature dependence of conductivity. Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, Sept. 10–15, 1995