Mixed Ionic-Electronic Conduction in HTcS
Application of HTcS materials as thin-film electrodes in solid state electrochemical systems, like solid oxide fuel cells (SOFC) and sensors, at elevated temperatures is a distinct possibility, provided that sufficient stability and electronic conductivity can be maintained. In addition, for these applications, HTcS materials need to exhibit also some oxygen ion conduction at the temperatures of operation. From the group of ceramic HTcS we have selected YBa2Cu3O7-x, 1, EuBa2Cu3O7-x,2 and La1.85Sr0.15CuO4, 3, for detailed study. These materials have been shown to exhibit variable stoichiometry in the oxygen sublattice which can be related with ionic conduction at elevated temperatures1–3.
KeywordsApparent Diffusion Coefficient Equivalent Circuit Solid Oxide Fuel Cell Transference Number Oxygen Sublattice
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