Electrical properties of the (Y2 − xLix)Ti2O7 − x samples with LiO0.5 self-flux

摘要: Abstract A series of (Y2 − xLix)Ti2O7 − x samples abbreviated as YLT-2L were prepared by the addition 2x moles LiO0.5 self-flux into parent compound, where x = 0.040 to 0.110. Preparation temperatures either 1300 or 1350 °C, depending on amount flux addition. However, Y2Ti2O7 had no co-existence; it was at highest temperature, 1600 °C. Relative densities all larger than 97%, but for Y2Ti2O7, 94.3(2)% only. By flux, preparation temperature reduced more 250 °C. Among samples, one with x = 0.070 total electrical conductivity (2.90(2) × 10− 4 S·cm− 1 700 °C) and lowest activation energy (0.99(1) eV). doping Li ion Y-site, oxygen vacancies created, although co-existence, still comparable compound reported Yamaguchi et al. (1998) Kobayashi (2002). At 500, 600 700 °C, ionic transference numbers (ti) found 1.00(2), 0.96(2) 0.90(3), respectively, did not vary substitution Contribution electronic due presence a small Ti3 + ions in investigated Ti K-edge XANES spectra.