Porous substrates for intermediate temperature SOFCs and in-cell reforming catalysts

The paper reviews results of development of new composite foam substrates with the graded structure for the intermediate temperature SOFC and structured catalysts of fuels reforming. Ni-Al substrates with porosity of 60-80% were prepared by compressive deformation of open cell metal foams followed by pack aluminizing. Testing in corrosive media revealed advantages of Ni-Al substrates over Fechraloy ones. Button-size thin film solid oxide fuel cell supported on this substrate demonstrated promising performance in the intermediate temperature range. These substrates were shown to be compatible with nanocomposite active components for the fuel reforming comprised of Ni-based alloys strongly interacting with perovskite/fluorite complex oxides with a high oxygen mobility and reactivity. High activity and coking stability of these structured catalysts in steam/autothermal reforming of natural gas, ethanol and acetone was demonstrated without a remarkable impact of heat and mass transfer. A close performance was demonstrated for fuel cells operating on wet H2 or in the mode of internal reforming of natural gas using these catalysts. A concept of the substrate with the graded pore structure and composition was offered.