Impedance studies on Pt/SrCe_0.95Yb_0.05O₃/Pt under dried and humidified air, argon and hydrogen

Arrhenius plots of conductivities and capacitances associated with the bulk, overall electrolyte, charge transfer and electrode processes taking place in a symmetrical cell with well-defined Pt electrodes and electrolyte based on the ceramic proton conductor, SrCe0.95Yb0.05O3, were obtained under wet and dry air, wet and dry hydrogen and wet and dry argon over the temperature range, 200 degrees C-800 degrees C. Results for all six gas atmospheres are discussed in order to gain insight into the conduction mechanisms taking place within the electrolyte and, especially, the conduction, sorption and diffusion processes occurring at the electrodes, in this model system. (c) 2006 Elsevier B.V. All rights reserved.