Electrical and sensing properties of indium-doped barium cerate

Systematic analysis of electrical characteristics of BaCe0.75In0.25O3-,5 (BCI25) sintered sample was performed in a dry and a wet argon atmosphere in the 250 degrees C-700 degrees C temperature range. The water vapor sensing properties of BCI25 porous film and its response and recovery times were investigated under different conditions of tem-perature and water vapor concentration. The 30 mu m thick film obtained from the powder calcined at 1050 degrees C exhibited sensitivity comparable to that of the sintered sample with a significantly shorter response and recovery times. While the sensitivity of the film gradually decreased with a decrease in partial pressure of water vapor (p (H2O)), a noticeable sensitivity was still observed at p(H2O) of 200 Pa. Decrease in conductivity depended logarithmically on the partial pressure of water with the slope of 0.52 that is close to the theoretical value. After several cycles, the reusability test proved an almost unchanged ratio between the impedance value in the dry and the wet Ar atmosphere (p(H2O) = 2.34 kPa), which implied that BCI25, having good stability and sensitivity, is a promising high-temperature humidity sensor.

Automated summary

Systematic analysis of electrical characteristics of BCI25 sintered sample was conducted and its water vapor sensing properties were investigated. The 30 μm thick film obtained from the powder exhibited comparable sensitivity but shorter response and recovery times. The sensitivity of the film gradually decreased with decreasing partial pressure of water vapor, but still maintained noticeable sensitivity at 200 Pa. The reusability test showed good stability and sensitivity of BCI25, indicating its potential as a high-temperature humidity sensor.