1.1.3 Al-doped TiO2 semiconductor gas sensor for NO2-detection at elevated temperatures
- 14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
- 1.1 High Temperature Gas Sensors I
- A. Yüce, B. Saruhan - Institute of Materials Research, German Aerospace Center (DLR) (Germany)
- 68 - 71
Al-doped TiO2 semiconductor layers were investigated as gas sensor for NOx detection at temperatures up to 800°C. Thin sensor layers were deposited by reactive magnetron sputtering technique from the metallic targets of Ti and Al under addition of oxygen onto the alumina substrates which consisted of screen-printed interdigited Ptelectrodes on the front and no heater at the backside. Al-content was adjusted to 6 atm. % in TiO2. The layers were characterized by XRD and SEM for phase and microstructural constituents. The phase content is consisted of anatase phase on deposition and was converted to rutile at temperatures exceeding 600°C. After annealing at 800°C for 3 hours in air, the sensor response is measured towards NO2 concentrations up to 200 ppm under dry and humid conditions (5 % H2O) in argon as the carrier gas. The sensors sensitivity and cross-sensitivity towards CO was also investigated. Al-doped TiO2 sensor layers exhibited very promising results for sensing NO2 selectively at temperatures exceeding 500°C.