The dc electrical conductivity, σ, of 60V
2O
5⋅10ZnO⋅30TeO
2 glass (mol%) prepared by press-quenching was measured under Ar and O
2 gas atmospheres and oxygen gas-sensing properties were investigated at temperatures ranging from 303 to 473K. Sigma at 443K in 100% Ar was determined to be 8.53×10
-4S·cm
-1, which was higher than σ in air (σ
443K=7.82×10
-4S·cm
-1), while σ
443K in 100% O
2 gas was 3.57×10
-4S·cm
-1, lower than the σ value in air. This means that V
4+ ions in the glass were oxdized by O
2 gas which diffused into the glass, resulting in an increase in V
5+ with time. The experimental relationship between σ and oxygen partial pressure
PO2 agreed well with the theoretical relation σ ∝
PO2-1/4. From data of dynamic change O
2 gas sensitivity,
S, defined as the ratio of dcresistivity in Ar gas to that in O
2 gas, at 473K was obtained to be 1.3 under 100% O
2 gas. Changes in σ by switching between 100% O
2 and 100% Ar were found to be reproducible. These changes were explained by the oxygen diffusion and desorption model. Good agreements was found between calculated σ and the experimental σ-
t relationship. From these discussions, it is concluded that the present tellurite glass has a potential applicability to O
2 gas sensor.
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