Oxygen adsorption properties on a palladium promoted La1−xSrxMnO3 solid oxide fuel cell cathode

Abstract

Surface reactions of O₂ molecules on a Sr-doped LaMnO₃ (LSM) cathode and Pd impregnated LSM cathode are investigated by the first principles method. A tetrahedral Pd₄ cluster is used to simulate the Pd particles on the LSM surface. The calculated adsorption energies demonstrate that the pre-adsorbed Pd facilitates O₂ adsorption on the surface. The bond length of adsorbed O₂ species and corresponding dissociation energies indicate that O₂ molecules on the Pd/LSM cathode surface can be dissociated more easily than on the pure LSM surface. The pre-adsorbed Pd (atom and cluster) can serve as an active center on the surface and enhance the electron transference properties during the oxygen reduction reactions.