Thermal Spraying and Performance of Graded Composite Cathodes as SOFC-Component

Porous compositionally graded composite cathodes containing (La 0.8 Sr 0.2 ) 0.98 MnO 3 (LSM) and ZrO 2 -12% Y 2 O 3 (YSZ) were prepared by vacuum plasma spraying (VPS) and flame spraying (FS) on prefabricated planar cells with 60 mm diameter. Besides mierostruetural observations their electrochemical behavior has been investigated by impedance spectroscopy. The results of graded cathodes compared with non-gradient- and bi-layered ones concerning the cathodic polarization resistance between 750 and 950°C are discussed.