Zirconia-based

The tape-casting method makes possible the fabrication of films in the region of several hundred micrometers thick. The mechanical strength allows the use of such a solid electrolyte as the structural element for devices such as the high-temperature solid oxide fuel cell in which zirconia-based solid electrolytes are employed both as electrolyte and as mechanical separator of the electrodes. 

J. Xue, and R. Dieckmann. Oxygen partial pressure dependence of the oxygen content of zirconia-based electrolytes in Ionic and Mixed Conducting Ceramics Second International Symposium 94-12, 191-208 (1994) ES Meeting San Francisco, California. 

Hu, Y. and Carr, P. W., Synthesis and characterization of new zirconia-based polymeric cation-exchange stationary phases for high-performance liquid chromatography, Anal. Chem., 70, 1934, 1996. 

Clausen, A. M., Subramanian, A., and Carr, P. W., Purification of monoclonal antibodies from cell culture supernatants using a modified zirconia-based cation-exchange support, /. Chromatogr. A, 831, 63, 1999. 

Another approach to increase HPLC speed is the use of higher temperatures. The viscosity of a typical mobile phase used in reversed-phase separation decreases as the column temperature is increased. This allows an HPLC system to operate at a higher flow rate without suffering too much from increased back pressure. Zirconia-based packing materials provide excellent physical and chemical stability. They have been used successfully for high-throughput bioanalysis at elevated temperatures.9... 

Activation Energy (Ea) and Conductivity (o) Values at High- and Low-Temperature Range for Some Zirconia-Based Electrolytes [10]... 

Lei and Zhu [63] found that adding 2.0 mol% Mn203 to llScSZ can inhibit the cubic-rhombohedral phase transformation in both oxidation and reduction atmospheres, and the codoped zirconia can reach nearly full density when sintered at temperatures as low as 850°C. The conductivity of 2Mn203-l IScSZ sintered at 900°C is 0.1 Scm-1 at 800°C. Figure 1.11 illustrates the conductivity of some zirconia-based ternary systems [32,42,57,63-67],... 

X. Song, A. Sayari, Sulfated zirconia-based strong solid-acid catalysts Recent progress,Cato/. Rev. Sci. Eng. 38, 329-412 (1996). 

TABLE 11.2. Physicochemical characteristics of stabilized zirconia-based catalysts ... 

P Ratnasamy, Crystalline, mesoporous ceria—zirconia based reforming catalysts for PEM fuel cells. Preprints Symp.—Am. Chem. Soc., Div. Fuel Chem. 46,635—640 (2001). 

Although most classical silica-ODS columns are not stable at temperatures much above 60°C (dependent on eluent conditions), columns made from other materials such as polymeric and zirconia-based phases have been used for high temperature work (see earlier text). 

The solid oxide electrolyte must be free of porosity that permits gas to permeate from one side of the electrolyte layer to the other, and it should be thin to minimize ohmic loss. In addition, the electrolyte must have a transport number for O as close to unity as possible, and a transport and a transport number for electronic conduction as close to zero as possible. Zirconia-based electrolytes are suitable for SOFCs because they exhibit pure anionic conductivity over a wide... 

O. Yamamoto, et ah, "Zirconia Based Solid Ion Conductors," The International Fuel Cell Conference Proceedings, NEDO/MITI, Tokyo, Japan, 1992. 

The stability of zirconia and zirconia-based packings also allows the use of these columns at an elevated temperature. The key advantage of this is the reduction in analysis time due to the reduction in the viscosity of the mobile phase. In addition, the much broader temperature range also permits a fine-tuning of the selectivity of a separation compared with silica-based packings. 

C is not recommended and high-temperature LC has not been rigorously explored. With the advent of thermally stable phases such as zir-conia-based stationary phases, temperatures in excess of 150°C can now be utilized. Many zirconia-based phases are available, so the stability of stationary phases is less of an issue. 

Bender, B., Shadwell, D., Bulik, C., Incorvat, L. and Lewis III, D. (1986). Effect of fiber coating and composite processing on properties of zirconia-based matrix SiC fiber composites. Am. Ceram. Soc. Bull. 65, 363-369. 

---