CATION DIFFUSION INTO A CGO ELECTROLYTE

摘要

The Ce_(0.9)Gd_(0.1)O_(1.95) (CGO) electrolyte/La_(1-x)Sr_xCo_yFe_(1-y)O_(3-δ) (LSCF) electrode couple shows promise for application in ceramic oxygen generators and solid oxide fuel cells. The oxygen ion transport properties of these materials have been extensively studied, but it is also important to investigate cation diffusion from the electrode into the electrolyte. This diffusion study has been undertaken using dynamic SIMS in combination with XRD to determine the solubility of iron and cobalt cations in CGO. The solubility of iron was found to be at least 2% and that of cobalt is less than 0.5%. The activation energy for diffusion of iron in CGO is (650±140) kJ/mol and for cobalt is (550±220) kJ/mol. No reaction products between CGO and LSCF were observed when the two compounds were sintered together at 1400℃ for SO hours.