| Summary: | 碩士 === 逢甲大學 === 材料科學與工程學系 === 103 === In the present study, Ce/Zr oxide powders were prepared from cerium nitrate hydrate (Ce(NO3)3) and zirconium nitrate hydrate (ZrO(NO3)2) by spray pyrolysis (SP) and co-precipitation (P). The as-prepared powders were screen-printed onto electrode-patterned substrates for oxygen sensing system. Then we consider the amount of palladium and silver. We try to find the best catalyst loadings. And two different powders with the composition effect The effects of addition amount of catalyst, electrical properties and oxygen sensitivity of thick films within a temperature range 500800°C were investigated. The responses of the specimens to oxygen partial pressure change at 600, 700 and 800°C were also discussed.
X-ray diffractometry identified the Ce/Zr oxide powders as a phase of ceria-zirconia solid solution. The powder obtained from spray pyrolysis was observed to be hollow spherical in shape with a wide range of particle size distribution, showing a well connecting behavior after sintering. The co-precipitated powders had a rod-like shape and exhibited a high surface area. However, the coating showed a island-like morphology after sintering. Suitable addition amount will help to the electrical performance and fast response performance on thick film of addition palladium or silver catalyst.
The different powder has its own different characteristics. By thick film composed of two processes, Its response performance has improved almost 30 percent compared to the original pure thick film. It will contribute to the oxygen sensor performance.
|
|---|
