Shaping of advanced asymmetric structures of proton conducting ceramic materials for SOFC and membrane-based process applications

A versatile fabrication process combining three techniques easy to scale up was successfully developed to prepare advanced multilayered structures integrating proton conducting ceramic materials. This enables the production of novel solid oxide fuel cells with proton conducting electrolytes (PCFCs) and asymmetric membranes designed as thin dense layers coated on thick porous mechanical supports. The manufacturing process makes use of ceramic powders synthesized by spray-pyrolysis using water-based solutions. Porous supports of membranes and anodes of PCFCs were prepared by tape-casting and their porosity was tuned by addition of corn starch filler. Membrane and electrolyte layers were prepared by spin-coating colloidal ceramic suspensions. A single coating-sintering step was carried out to produce gas tight layers with thickness ranging from 4 to 26 μm. Cathodes of PCFCs were screen-printed using commercial Pt ink. This paper describes the successful preparation of SrCe0.95Yb0.05O3−δ asymmetric membranes and novel concepts of PCFCs integrating BaZr0.9Y0.1O3−δ and La0.995Sr0.005NbO4+δ electrolytes.