Non-stoichiometry, Fermi energy and work function of (La,Sr)MnO3. II. Verification of theoretical model

A model describing the relationship between nonstoichiometry and Fermi ener gy was used to determine the effect of oxygen partial pressure on semicondu cting properties of perovskite-type oxide materials, such as (La,Sr)MnO3. S pecifically, this model was used to determine the electrical effects at the gas/solid interface for the oxygen/metal oxide system with specific rr:spe ct to oxygen non-stoichiometry and oxygen chemisorption. It was found that oxidation of (La0.8Sr0.2)MnO3 at both 1023 and 1073 K, corresponding to cha nges of p(O-2) in the range 10 and 21 kPa, results in the formation of a ch emisorption-related surface potential barriers that assumes 0.165 V while o xidation at 1123 K leads to oxygen incorporation without changes in chemiso rption equilibrium. (C) 2001 Elsevier Science Ltd. All rights reserved.