2.3.2 Photo-assisted Aromatic VOC Sensing by a p-NiO:Li/n-ZnO Transparent Heterojunction Sensor Element
- Event
- 14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
Nürnberg/Nuremberg, Germany - Chapter
- 2.3 Metal Oxide-based Gas Sensors II
- Author(s)
- Y. Nakamura - Department of Applied Chemistry, School of Engineering, The University of Tokyo (Japan), Y. Morita, Y. Ishikura - Department of Materials Science and Ceramic Engineering, Shonan Institute of Technology (Japan), H. Takagi - Department of Physics, School of Science, The University of Tokyo (Japan), S. Fujitsu - Materials and Structures Laboratory, Tokyo Institute of Technology (Japan)
- Pages
- 189 - 192
- DOI
- 10.5162/IMCS2012/2.3.2
- ISBN
- 978-3-9813484-2-2
- Price
- free
Abstract
p-NiO/n-ZnO transparent heterojunction diode is prepared by the continuous film deposition using RF magnetron sputtering technique and processed into a chemical sensor element by photolithography pattering and chemical etching. This structurally designed p-NiO/n-ZnO junction diode, whose junction interface is exposed to the atmosphere, has a response to VOCs (volatile organic compounds) in atmosphere. Furthermore, its VOC sensing performance is extremely enhanced when the sensor element is operated under deep UV light irradiation (<300nm). Independent of the polality of the applied bias, the current passing through the junction interface rapidly decreases by the introduction of benzene or other aromatic VOCs. Photo-driven electron transport between photoexcited VOC adsorbates and valence band (VB) of p-NiO plays an important role for this sensor operation.