Conducting properties, thermal expansion, and chemical stability of La1.8-XPrXSr0.2CuO4-delta (x = 0.2; 0.4) related to the K2NiF4-type structure have been investigated in order to estimate their appropriateness to be used as a cathode material for solid oxide fuel cells. Electrical conductivity of Lai(8-X)Pr(X)Sr(0.2)CuO(4-delta) demonstrates metallic-like behavior in the temperature range of 100-900 degrees C at variable oxygen partial pressure (pO(2) = 10(-3)-1 atm), and reaches 50 S/cm at 750 degrees C in air. The cuprates display thermal expansion coefficients (TECs) of about 14.10(-6) K-1 that are compatible with La(0.8)Sr(0.2)Da(0.85)Mg(0.15)O(3-delta) (LSGM) and Ce0.9Gd0.1O1.95 (GDC) solid electrolytes. The electrocatalytic activity study of La1.6Pr0.2Sr0.2CuO4-delta electrode deposited on GDC as well as LSGM shows that the lowest polarization resistance is achieved in case of deposition of the electrode on GDC electrolyte. (C) 2015 Elsevier B.V. All rights reserved.