High-Temperature Proton Conductors Based on Strontium and Barium Cerates: The Interphase Exchange and Diffusion of Oxygen

摘要

Kinetic parameters of interphase exchange of oxygen in high-temperature proton conductors BaCe_(0.95)Nd_(0.05)O_(3-δ) and SrCe_(0.95)Y_(0.05)O_(3-δ) are determined using an isotope exchange method in the temperature range 630–820℃ at oxygen pressures of 2.7–13.3 gPa and diffusion coefficients for oxygen are calculated. Effective energies of activation of oxygen exchange and diffusion coefficients for oxygen are calculated. Dependence of exchange characteristics and the diffusion coefficients on the oxygen pressure in the gas phase is investigated. The oxygen exchange on the surface of studied oxides is shown to proceed only with the participation ofoxygen of the oxides, which causes high rates of interphase exchange of oxygen of studied cerates of barium andstrontium. It is shown that the obtained data satisfactorily agree with those found in the relevant literature.