Application of work function measurements for surface monitoring of oxide electrode materials (La,Sr)(Co,Mn,Fe)O-3

This paper reports application of the work function (WF) measurements for s urface monitoring of perovskite-type electrode materials, such as (La,Sr)Mn O3, (La,Sr)CoO3, (La,Sr)FeO3 as well as Co-doped and Fe-doped (La,Sr)MnO3, during oxidation and reduction. The WF changes during oxidation at 1073 K a re considered in terms of several processes of different rate of appearance , such as (a) oxygen chemisorption, (b) oxygen incorporation into the oxide lattice and related changes of Fermi energy, (c) non-stoichiometry-induced transient oxygen chemisorption (desorption), and (d) structural changes wi thin the surface layer that are induced by changes in oxygen partial pressu re. (C) 2001 Elsevier Science Ltd. All rights reserved.