The appropriate equations governing proton incorporation into perovskite oxides with an emphasis on high-temperature proton conductors were reviewed. The prototypical compound SrCe0.95Y0.05O3-δ was considered in detail. The mathematical approach of Poulsen was applied and the defect concentrations were modeled with a C language routine. A cluster-defect model was not considered here. Defect concentrations were calculated as a function of water vapor pressure and O partial pressure. The solutions were presented in the form of 2- and 3-dimensional graphs of defect concentrations versus water vapor and O partial pressures. Their physical meanings were explained by pertinent proton incorporation equations. Effects of water vapor pressure and A/B ratio on the n–p transition point were simulated.

Defect Chemistry Modeling of High-Temperature Proton-Conducting Cerates. S.J.Song, E.D.Wachsman, S.E.Dorris, U.Balachandran: Solid State Ionics, 2002, 149[1-2], 1-10