D2.4 - Effect of Doping at TiO2-Nanotubular Gas Sensors
- SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
- Proceedings SENSOR 2011
- D2 - High Temperature Sensors II
- Y. Gönüllü, A. Yüce, G. Montragón-Rodrígues, B. Saruhan - German Aerospace Center, Köln (Germany), F. Bayata, M. Ürgen - Istanbul Technical University, Maslak (Turkey)
- 551 - 553
Relying on its unique properties, titaniumdioxide is employed in a versatility of applications, gas sensing being one of them. Low temperature synthesis of doped TiO2-coatings and their nano-structuring enhance these properties. It is reported that the use of one-dimensional (1-D) nanostructures instead of nano-crystalline films yields more than 2-fold increase in efficiency by improving the sensing properties. Nanotubular sensing electrodes improve sensing performance due to offered high surface to volume ratio to enable strong interaction between the surrounding gas and the sensing material.
This work reports the synthesis of coatings having TiO2-nanotubes prepared by using template-free synthesis method. Additionally, the doping of TiO2-nanotubes with trivalent (Al3+) and transient metals (Cr3+) has been carried. For that purposes different techniques were employed. Development of microstructure and phase sequences with composition and temperature were analysed. Using these coatings, gas-sensor-devices were fabricated and their sensing properties were analyzed towards reducing and oxidizing gases. For obtainment of the sensor signal at HT a pre-treatment is required. Sensor devices were tested under various gas concentrations and temperatures. High sensitivity and short response times are the typical characteristics of these sensors Their properties obtained with various compositions and synthesis methods were compared.