Kinetics of metal-oxygen reaction by solid oxide electrolyte cells

Chronopotentiometric curves, generated by galvanostatic single steps, applied to solid oxide electrolyte cells, were analyzed on the basis of a dimensionless equation derived on the assumption that a scale of oxide grows at one of the electrode-electrolyte interfaces.  This process is rate limiting for developing the charge transfer-diffusion overvoltage, and Wagner's theory, on tarnishing under retarding elec. field conditions, was assumed for treating the kinetics of the growing scale.  At const. temp., the oxidn. rate and oxidn. rate const. were measured as a function of the O partial pressure in the range of pressures near the equil. pressure of the metal-oxygen system.