Chromite compounds conductivity

FIGURE 4.3 Conductivity of chromite compounds in reducing atmospheres at 700°C [41,... 

An industrial process to prepare those materials with well controlled composition has been developed, particle size, surface area, and phase purity. The resulting application properties are superior to conventional products obtained by solid state routes. Table 9-5 gathers the typical characteristics of such compounds. An example of a study conducted on lanthanum chromite is given in reference 32. New lanthanum manganite products were also patented [33]. 

The perovskite lanthanum chromite (LaCr03) is one of the exceptional ceramic compounds that are chemically very resistant to both oxidizing and reducing ambients. Moreover, being an electronic conductor, it is eminently suitable as a bipolar connector in solid oxide fuel cells. It is evident that the thermal expansion coefficients of the different components in a fuel cell (electrolyte, electrodes, bipolar connector) must be closely matched. Doping the chromite with strontium or magnesium ions is necessary to increase its electronic conductivity as well as its sinter activity. 

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