Al-foam based composites for metal supported SOFC with improved resistance to degradation

Solid oxide Fuel Cells are approaching commercial exploitation thanks to joint efforts by research institutions and industries. Such a combination profits from scientific advancements in materials design and optimization. At the moment, research is targeting the recognized limitation of SOFC, basically consisting in excessive performance degradation over the expected lifetime of devices. Several innovations have been explored to overcome such limitation by reducing operating temperature and improving stability of materials. Second generation cells, anode-supported, make extensive use of Ni as catalytic material for H2 oxidation reaction, while third generation cells, metal-supported, are commonly fabricated with Ni foam as support. Due to this reason, both types suffer from conductivity loss on redox cycling and exposure to fuels with higher S content, as in biogas. One possible approach to significantly reduce or completely avoid the use of Ni is the development of a new kind of support made of an Al-forming foam impregnated with an electronic conducting ceramic phase. Within the European project EVOLVE, a combination of NiCrAl foam and n-doped SrTiO3 are being studied as potential substrates for metal supported SOFC, with the aim to realize a composite with high resistance to oxidation and good conductive properties. The properties of single components, the compatibility among different phases and the behaviour of composites under RedOx cycling are reported.