Synthesis and Ionic Conductivity of KAlSi3O8

In this study, KAlSi₃O₈ was synthesized by a solid-phase reaction at 900, 1000 and 1100 °C, using K₂CO₃, Al₂O₃ and SiO₂ as the starting materials. The powder X-ray diffraction profile of the compound thus prepared was confirmed to contain a mixture of crystalline and glass phases. In addition, a higher sintering temperature of greater than 1000 °C possibly led to the decrease in the crystalline phase. From the temperature dependence of dc conductivity, activation energies for ionic transport were estimated to be 0.79–0.84 eV. The frequency-dependence of the real part of electrical conductivity suggests that the mechanism of ionic transport in the dispersion region possibly depends on the crystallinity of KAlSi₃O₈.