To investigate the influence of A-site stoichiometry on phase stability and electrical conductivity of the perovskite based series La-S(Ni0.59Fe0.41)O3-delta for cathode current collection in solid oxide fuel cells, X-ray diffraction and DC electrical conductivity studies were performed on samples, prepared by the glycine nitrate combustion method. The chemical compatibility of La-0.99(Ni0.59Fe0.41)O3-delta with the cathode material (La0.85Sr0.15)(0.91)MnO3-delta and the electrolyte Y2O3-doped ZrO2 (8 mol%) was likewise studied by X-ray diffraction and scanning electron microscopy. Small deviations (similar to 1 at.%) in the A-site stoichiometry of the perovskite did not result in significant change to the electrical conductivity. Extensive reaction between La-0.99(Ni0.59Fe0.41)O3-delta and 8 mol% Y2O3 doped ZrO2 after sintering was observed by X-ray diffraction. Reaction between La-0.99(Ni0.59Fe0.41)O3-delta and (La0.85Sr0.15)(0.91)MnO3-delta resulted in a single perovskite material when the compounds were cosintered. The interface between a screen-printed layer of La-0.99(Ni0.59Fe0.41)O3-delta and a layer of Ce0.9Gd0.10O3-delta/(La0.85Sr0.15)(0.91)MnO3-delta composite has been investigated and the extent of the reaction zone determined by energy dispersive X-ray spectroscopy. (c) 2005 Elsevier B.V. All rights reserved.