Perovskites and Related Mixed Oxides for SOFC Applications

Perovskites and Related Mixed Oxides for SOFC Applications 

Edited by Pascal Granger, Vasile I. Parvulescu, Serge Kaliaguine, and Wilfrid Prellier. 

A fuel cell is a device that allows the direct conversion of the chemical energy of fuels to electricity. Fuel cells fed with a hydrogen or syngas fuel have long been considered as a promising approach for electricity generation because of their 

Carbonate and phosphate fuel cells have found limited applications because of the lack of effective ways in dealing with liquid electrolytes and in further 

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Some perovskite-type oxides show protonic conduction and are useful for hydrogen-related electrochemical devices, including application to solid oxide fuel cells (SOFCs). Iwahara et al. reported protonic conductivity of strontium-cerate-based perovskite-type oxides in 1981 [1], Since that time, various perovskite-type proton-conducting oxides have been found. For use of the proton-conducting perovskite oxides, we should understand not only their merits but also their weak points. This chapter concerns the protonconducting properties of typical cerium- and zirconium-containing perovskite oxides from the points of view of conductivity, stability, electrode affinity, and dopant effect. Mixed conduction occurring in a special composition of the perovskite oxide is also introduced. 

In this chapter the technological development in cathode materials, particularly the advances being made in the material s composition, fabrication, microstructure optimization, electrocatalytic activity, and stability of perovskite-based cathodes will be reviewed. The emphasis will be on the defect structure, conductivity, thermal expansion coefficient, and electrocatalytic activity of the extensively studied man-ganite-, cobaltite-, and ferrite-based perovskites. Alterative mixed ionic and electronic conducting perovskite-related oxides are discussed in relation to their potential application as cathodes for ITSOFCs. The interfacial reaction and compatibility of the perovskite-based cathode materials with electrolyte and metallic interconnect is also examined. Finally the degradation and performance stability of cathodes under SOFC operating conditions are described. 

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