Layered perovskite oxide NdBa0.5Sr0.5Co2O5+x is investigated as a cathode material for intermediate-temperature solid oxide fuel cells. The NBSC cathode is chemically compatible with the electrolyte La0.9Sr0.1Ga0.8Mg0.2O3-delta (LSGM) at temperatures below 1000 degrees C. It is metallic in nature and the maximum and minimum conductivities are 1368 S cm(-1) at 100 degrees C and 389 S cm(-1) at 850 degrees C. The area specific resistance (ASR) value for the NBSC cathode is as low as 0.023 Omega cm(2) at 850 degrees C. The electrolyte-supported fuel cell generates good performance with the maximum power density of 904, 774 and 556 mW cm(-2) at 850.800 and 750 degrees C, respectively. Preliminary results indicate that NBSC is promising as a cathode for IT-SOFCs. (C) 2010 Elsevier B.V. All rights reserved.