Theoretical Prediction of the Vapor Pressure of Solid Oxide Fuel Cell Components

Abstract

Due to the high operating temperature of solid oxide fuel cells, various chemical reactions can lead to degradation, for instance, based on Cr2O3 gas phase evaporation from the interconnect and subsequent reaction with SrO which originates from LSCF cathodes. Therefore, investigations of the potential chemical reactions and the sublimation process play an extremely important role to study the related chemical reactions in SOFCs. Here we propose a practical physical model based on density functional theory calculations and statistical mechanics to predict the vapor pressure of pure substances. This model is allowed to extend the thermodynamic database and to analyze the resulting chemical reactions inducing the new phase formation which leads to the degradation of SOFCs. These investigations serve as a theoretical basis to understand and reduce degradation phenomena from a thermodynamic and kinetic perspective.