Study of oxygen ion transport in acceptor doped samarium cobalt oxide.

Dense samples of the perovskite SmSrCoO (where x=0, 0.2, 0.4, 0.5 and 0.6) have been prepared. The samples wereO/O isotopically exchanged at a variety of temperatures between 500°C and 900°C. Subsequent analysis of the diffusion profile using Secondary Ion Mass Spectrometry (SIMS) allowed the oxygen self-diffusion coefficient, D*, and surface exchange co-efficient, k, to be determined. From the temperature dependence of these parameters the activation energies for both processes were evaluated. The surface coverage of samarium, cobalt and oxygen in SmCoO was determined from calibration samples using Low Energy Ion Scattering (LEIS). LEIS was used to determine the effect of strontium doping on the surface composition and theO-concentration at the surface of a number of theO-exchanged samples. [ABSTRACT FROM AUTHOR]