Kinetics of Oxygen Surface Exchange on Epitaxial Ruddlesden-Popper Phases and Correlations to First-Principles Descriptors

J Phys Chem Lett. 2016 Jan 21;7(2):244-9. doi: 10.1021/acs.jpclett.5b02423. Epub 2016 Jan 5.

Abstract

Through alignment of theoretical modeling with experimental measurements of oxygen surface exchange kinetics on (001)-oriented La2-xSrxMO4+δ (M = Co, Ni, Cu) thin films, we demonstrate here the capability of the theoretical bulk O 2p-band centers to correlate with oxygen surface-exchange kinetics of the Ruddlesden-Popper oxide (RP214) (001)-oriented thin films. In addition, we demonstrate that the bulk O 2p-band centers can also correlate with the experimental activation energies for bulk oxygen transport and oxygen surface exchange of both the RP214 and the perovskite polycrystalline materials reported in the literature, indicating the effectiveness of the bulk O 2p-band centers in describing the associated energetics and kinetics. We propose that the opposite slopes of the bulk O 2p-band center correlations between the RP214 and the perovskite materials are due to the intrinsic mechanistic differences of their oxygen surface exchange kinetics and bulk anionic transport.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.