Applications of Zirconia

Zirconia sensors have been used primarily in the exhaust system of automobiles to control the air-to-fuel ratio for meeting the federal requirements on such noxious gases as carbon monoxide, methane and nitrogen oxides. The applicability of zirconia sensors for this particular application is based on the assumption that, under thermodynamic equilibrium, the partial pressure of oxygen in the exhaust gas depends primarily on the air-to-fuel ratio. To compensate for the fact that in reality equilibrium is not reached, catalytic platinum electrics are incorporated in the zirconia sensor design [Stevens, 1986]. In the zirconia sensor, the outside of the zirconia tube is exposed to the exhaust gas while the inside is exposed to the ambient air as a reference atmosphere. 

Birkby, I. and Stevens, R., Applications of zirconia ceramics, in Key Engineering Materials, 122-124,527-552, Trans. Tech. Publications, Switzerland (1996). 

Zirconia aerogels are known to possess several properties needed for applications as a catalyst or catalyst support. The most reported catalytic applications of zirconia aerogels are related to the modification of their surfaces by metals or ions, in particular sulfate, phosphate, and tungstate anions. 

Sasaki, K., and Maier, J. (2000). Re-analysis of defect equilibria and transport parameters in Y203-stabilized Zr02 using EPR and optical relaxation. Solid State Ionics 134 303-321. Birkby, I., and Stevens, R. (1996). Applications of zirconia ceramics. Key. Eng. Mater. 122-124 327-332. 

Other Applications of Zirconia Nanomaterials in the Life Sciences... 

With regards to the application of zirconia nanomaterials in the life sciences, ceramics based on transformation-toughened zirconia are today widely used in joint replacement surgery, due to their bioinertness and excellent mechanical properties, although the complex structural and mechanical properties of zirconia, and the long-term mechanical behavior of these ceramics in vivo are still not... 

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