Electrolytes and ion conductors for solid oxide fuel cells (SOFCs)
N. Preux, A. Rolle and R.N. Vannier, Ecole Nationale Supérieure de Chimie de Lille, France
The most commonly used electrolyte in solid oxide fuel cells (SOFCs) is zirconia. However, pure zirconia is a poor oxide ion conductor and zirconium of valence IV must be partly substituted by cation with lower valence to allow oxide ion diffusion. Aside from lanthanum silicates with apatite structure, the structure of most of the oxides which have been studied as possible electrolyte derive from either the fluorite or the perovskite. They must be stable under both oxidizing and reducing atmospheres, as dense and thin as possible, and act as electronic insulator with ...