Anode SOFCs Produced by Suspension Plasma Spraying: Interests and Prospects

In order to achieve Solid Oxide Fuel Cells (SOFC) with reduced costs, the atmospheric plasma spray process (APS) could be an attractive technique. However, it is difficult to produce plasma sprayed coatings with the appropriate porosity for the electrodes and full density for the electrolyte. The spray process has been adapted by providing a suspension or a powder as feedstock material combined with optimized spray conditions to manufacture SOFC layers with required compositions, microstructures and properties. Suspensions or powders were injected in a plasma jet originating from a conventional torch (F4) implementing external devices. By using optimized suspensions of nickel oxide (NiO) and yttria stabilized zirconia (YSZ) in ethanol, porous anodes have been produced with thicknesses around 50 µm. By the same way aqueous suspensions of yttria stabilized zirconia (YSZ) powders have been prepared to achieve a fine layer as electrolyte to produce the first half cells and the porous cathode layers based on lanthanum strontium manganite (La_0.8Sr_0.2MnO₃ or LSM) have been manufactured by conventional atmospheric plasma spraying of powders.