| Autor: |
Koji Amezawa, Yoichi Tomii, Naoto Kitamura, Naoichi Yamamoto, Nobuyuki Takahashi |
| Rok vydání: |
2004 |
| Předmět: |
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| Zdroj: |
Solid State Ionics. 175:575-579 |
| ISSN: |
0167-2738 |
| DOI: |
10.1016/j.ssi.2004.02.079 |
| Popis: |
Electrical conduction in lanthanum orthoborates LaBO 3 with the orthorhombic aragonite-type structure (S. G.: Pnam) was investigated by using conductivity measurements under 0.4–5 kPa of p (H 2 O) and 0.01–100 kPa of p (O 2 ) at 500–930 °C. From humidity dependence and H/D isotope effect of the conductivity, it was found that LaBO 3 exhibited dominantly protonic conduction under wet conditions by substituting Sr for La. Results of conductivity measurements under various p (H 2 O) and p (O 2 ) suggested that the contribution of electron hole conduction became significant as temperature increased, p (O 2 ) increased and p (H 2 O) decreased, although protonic conduction was estimated as predominant under the conditions used. The conductivities of the 1 mol% Sr-doped LaBO 3 were 1×10 −5 –2×10 −4 S cm −1 under moisturized conditions at 500–930 °C. The conductivity behaviors as well as the conductivity values of the Sr-doped LaBO 3 with the aragonite-type structure were quite similar to those of the acceptor-doped rare earth orthophosphates, indicating a similar proton conduction mechanism in these oxoacid salts. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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Full Text from ScienceDirect