多孔質セラミックスxLi₂O・Al₂O₃・2SiO₂を用いた湿度センサ

抄録

Humidity sensor elements using xLi₂O⋅Al₂O₃⋅2SiO₂ porous ceramics were produced and the effect of sintering temperatures and Li₂O(x) contents on the humidity sensitivity, the response time, and the long-term stability was investigated. Eucryptite (Li₂O⋅Al₂O₃⋅2SiO₂) sintered at 1100°C was desirable for a humidity sensor with respect to sensitivity, linearlity, hysteresis, and long-term stability. The impedance changed from 10⁷ to 10⁴Ω⋅cm, linearly in the humidity range of 20-90% RH. The response time was about 3min with a quick change of relative humidity from 90 to 60% RH. Detected relative humidity by using Li₂O⋅Al₂O₃⋅2SiO₂ was accurate within ±2% RH even after 300 days storage in a laboratory air.