A High Temperature Capacitive Humidity Sensor Based on Mesoporous Silica

作者：Wagner Thorsten^*; Krotzky Soeren; Weiss Alexander; Sauerwald Tilman; Kohl Claus Dieter; Roggenbuck Jan; Tiemann Michael

来源：Sensors (Switzerland), 2011, 11(3): 3135-3144.

DOI：10.3390/s110303135

• capacitive sensor
• humidity
• high temperature
• mesoporous silica

Capacitive sensors are the most commonly used devices for the detection of humidity because they are inexpensive and the detection mechanism is very specific for humidity. However, especially for industrial processes, there is a lack of dielectrics that are stable at high temperature (>200 degrees C) and under harsh conditions. We present a capacitive sensor based on mesoporous silica as the dielectric in a simple sensor design based on pressed silica pellets. Investigation of the structural stability of the porous silica under simulated operating conditions as well as the influence of the pellet production will be shown. Impedance measurements demonstrate the utility of the sensor at both low (90 degrees C) and high (up to 210 degrees C) operating temperatures.

• 出版日期2011-3