Electrical properties of La10Si6O27-based oxides

Dense solid electrolytes based on lanthanum silicate, La10Si6O27 (LSO) were fabricated and their electrical conducting properties were studied in detail under various atmospheres, including H2O- or D2O-humidified argon. The family showed almost P(O2)-independent conductivity, while a slight increase in conductivity with increasing P(O2) was observed in the high temperature region. The ionic transport number evaluated from the O2/Ar oxygen concentration cell was higher than 0.964 at 1073–1273 K. The current–voltage characteristic of the fuel cell employing the dense LSO electrolyte was also investigated.