Scanchum-doped lanthanum strontium manganate La0.8Sr0.2Mn1-xScxO3-delta (LSMS) combined with YSZ as composite cathode for ancide-supported solid oxide fuel cell is investigated. The LSMS powders are prepared using the modified Pechini method. The XRD and H-2-TPR results reveal that non-stoichiometric defects are introduced into the perovskite lattice of LSMS samples as a result of Sc substitution, which leads to increased oxygen ion mobility in the Sc containing samples. But high level doping of Sc may results in the segregation of the Sc2O3 secondary phase at elevated temperature. The cells with the LSMS-containing cathodes exhibit higher performances, especially at lower temperatures, which can be ascribed to the increased oxygen anionic vacancies in the LSMS. (C) 2008 Elsevier B.V. All rights reserved.