NO
2 emission is mostly related to combustion processes, where gas temperatures exceed far beyond 500 °C. The detection of NO
2 in combustion and exhaust gases at elevated temperatures requires sensors with high NO
2 selectivity. The thermodynamic equilibrium for NO
2
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NO
2 emission is mostly related to combustion processes, where gas temperatures exceed far beyond 500 °C. The detection of NO
2 in combustion and exhaust gases at elevated temperatures requires sensors with high NO
2 selectivity. The thermodynamic equilibrium for NO
2/NO ≥ 500 °C lies on the NO side. High temperature stability of TiO
2 makes it a promising material for elevated temperature towards CO, H
2, and NO
2. The doping of TiO
2 with Al
3+ (Al:TiO
2) increases the sensitivity and selectivity of sensors to NO
2 and results in a relatively low cross-sensitivity towards CO. The results indicate that NO
2 exposure results in a resistance decrease of the sensors with the single Al:TiO
2 layers at 600 °C, with a resistance increase at 800 °C. This alteration in the sensor response in the temperature range of 600 °C and 800 °C may be due to the mentioned thermodynamic equilibrium changes between NO and NO
2. This work investigates the NO
2-sensing behavior of duplex layers consisting of Al:TiO
2 and BaTi
(1-x)Rh
xO
3 catalysts in the temperature range of 600 °C and 900 °C. Al:TiO
2 layers were deposited by reactive magnetron sputtering on interdigitated sensor platforms, while a catalytic layer, which was synthesized by wet chemistry in the form of BaTi
(1-x)Rh
xO
3 powders, were screen-printed as thick layers on the Al:TiO
2-layers. The use of Rh-incorporated BaTiO
3 perovskite (BaTi
(1-x)Rh
xO
3) as a catalytic filter stabilizes the sensor response of Al-doped TiO
2 layers yielding more reliable sensor signal throughout the temperature range.
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