Metal-supported solid oxide fuel cells are expected to offer several potential advantages over conventional anode (Ni-YSZ) supported cells, such as increased resistance against mechanical and thermal stresses and a reduction in materials cost. When Ni-YSZ based anodes are used in metal supported SOFC, electrode material from the active anode layer may interdiffuse with the metallic support during sintering. The purpose of this work is to illustrate how the interdiffusion problem can be circumvented by using an alternative anode design based on porous and electronically conducting layers, into which electrocatalytically active materials are infiltrated after sintering. The paper presents the recent results on the electrochemical performance and durability of the novel planar metal-supported SOFC design. The results presented in the paper show that the novel cell and anode design has a promising performance and durability at a broad range of temperatures and is especially suitable for intermediate temperature operation.

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The embedded-atom method (EAM) [M.S. Daw and M. I. Baskes, Phys. Rev. Lett. 50, 1285(1983; Phys. Rev. B 29, 6443 (1984)] is applied to surface segregation and surface relaxation of binary alloys. This method needs no ad hoc size-mismatch strain energy and can handle arbitrary interlayer distances at the surface. Three low-index faces of platinum-nickel alloys are studied.Previously, low-energy electron diffraction investigations have established a face-related segregation on platinum-nickel alloys, with platinum enrichment on the (111) surface and nickel enrichment on the (110) surface. This work shows that EAM is capable of reproducing the experimentally determined segregation and relaxation with a good accuracy. In addition, EAM predicts the existence of a metastable concentration profile on the Pto &Nio 5(110) surface. I. ImRuDUCTIOXIn the present paper the embedded-atom method' (EAM) is used to describe the energetics of atoms in substitutionally disordered binary alloys, where both multilayer segregation and multilayer relaxation are found to occur at the surface. The energy expression in the EAM is a function of atomic distances. This makes it possible to find both the composition and the geometry near the surface. A statistical approach is used to simulate the equilibrium state of the alloys.In this work the EAM is applied to platinum-nickel alloys which show a face-related segregation ' with platinum enrichment on the (111)surface and nickel enrichment on the (110) surface. The (110) surface is particularly interesting because of the large contraction of the spacing between the first and second layers. It is well known that platinum-nickel alloys are exceptions from simple segregation criteria, which are successfully applied to a large number of other alloys. The EAM gives a quantitatively correct description of the (111) surface of platinum-nickel alloys with respect to both concentration profile and surface relaxation. For the (110) surface the EAM indicates the existence of two equilibrium states of segregation. One state is in good agreement with experiment, and the other can be interpreted as a metastable state which may be obtained by a special treatment of the crystal. It is concluded that a good description of the surface relaxation is crucial for the calculation of segregation. The EAM is a semiempirical model, proposed by Daw and Baskes, ' for the energy in a pure metal or in an alloy. This model is used in a number of different applications, ' ' ' where various bulk and surface properties are studied. In a previous work Foiles' used Monte Carlo simulations with energies from the EAM to predict both concentrations and atomic positions for copper-nickel alloys. Surface energies and surface relaxations for pure metals are obtained, and the surface reconstructions on Pt(110) (Ref. 11) and Au(100) (Ref. 14) are predicted. These results make the EAM a promising model for energies at surfaces of pure metals and alloys.Surface segregation is of great technological importance. The properties of alloy su...

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