The capacitance of mixed oxides consisting of oxides with different semiconducting properties decreases upon exposure to NO. In particular, the mixed oxide NiO-WO3 exhibits an extremely large capacitance decrease upon exposure to 100 ppm NO, but a period longer than 30 min is required to recover the original capacitance level after changing to air without NO. On the other hand, the mixed oxide WO3-ZnO exhibits a large capacitance decrease upon exposure to NO and its capacitance decreases with increases in the NO concentration up to 300 ppm. Therefore, the concentration of nitrogen oxide can be analysed by the capacitance of these mixed oxides.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry
- Electrical and Electronic Engineering