کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1296686 | 1498349 | 2010 | 7 صفحه PDF | دانلود رایگان |

Nominally undoped TiP2O7 and TiP2O7 with 2 mol-% substitution of Ti by Al were synthesized from TiO2 (Al2O3) and H3PO4(aq), sintered at 1050 °C, and characterized by XRD, TEM and SEM. The electrical conductivity was investigated at 300–1000 °C as a function of p(O2), p(H2O), and p(D2O). The material's phase transition around 700 °C is clearly visible in the conductivity curves. Al substitution hardly increased the conductivity. The conductivity was higher in H2O- than in D2O-containing and dry atmospheres, indicating the dominance of proton conduction. The conductivity was accordingly mainly independent of p(O2). A slight increase in the conductivity with decreasing p(O2) at the highest temperatures was indicative of a minor contribution of n-type electronic conduction. The p(H2O) and temperature dependencies of the conductivity have been modelled as a sum of proton and electron partial conductivities under a situation with protons charge compensated by oxygen interstitials as dominating defects.
Journal: Solid State Ionics - Volume 181, Issues 11–12, 29 April 2010, Pages 510–516