Carbon monoxide gas sensor based on titanium dioxide nanocrystalline with a langasite substrate

摘要

Titanium dioxide (TiOsub2/sub) and gold doped TiOsub2/sub (Au-TiOsub2/sub) thin films on langasite (LGS) substrates were employed for carbon monoxide (CO) sensing. These two types of sensors have interdigital electrodes with Ti, Ni and Au metallization film. Thin films of TiOsub2/sub were deposited using the radio frequency (RF) magnetron sputtering method. Both TiOsub2/sub and Au-TiOsub2/sub based gas sensors were exposed to low concentrations of CO gas in synthetic air at a temperature range between 230°C and 320°C and their electrical conductivity were measured. It has been observed that the device sensitivity is much greater for the Au-TiOsub2/sub based gas sensor. The response time of the sensor is shorter than that of commercial conductometric CO sensors.