Properties of 3-15 mol% YSZ Materials

The ionic conductivities of yttria-doped zirconia (YSZ) materials are interesting because of their use in solid oxide fuel cells (SOFCs). Their main application is as electrolyte materials, but YSZ particles are also used for mixing with nickel particles in the SOFC anode to create a zone containing both electronically and ionically conducting particles (or grains) in order to extend into the anode the "triple-phase-boundary" (TPB) accessible to all three types of species: 1) gaseous reactants and products, 2) oxygen ions and 3) electrons, necessary for the anodic electrode reaction to proceed. Doing this makes the TPB larger and therefore reduces the part of the cell internal resistance which is due to slow anodic reaction. Furthermore, the smaller the particles in this binary Ni/YSZ mixture, the larger will be the TPB for a given volume of anode.