The performance of Nd2-xLaxNiO4+delta as a cathode material for solid oxide fuel cell (SOFC) was evaluated in this paper. Substitution of smaller Nd3+ ion for La3+ in La2NO4+delta increased the retention of mobile interstitial oxygen defects (O-i" ions). The concentration of the O-i" ions in Nd2NiO4+delta was stabilized at delta approximate to 0.12 at 800 degrees C in air after thermal cycling. As a mixed oxide-ion/clectronic conductor (MIEC), Nd2NiO4+delta gave a performance comparable to that of the best perovskite cathode material, SrCo0.8Fe0.2O3-delta (SCF), for the Sm-doped cerin (SDC) electrolyte-supported SOFC. However, the Nd2NiO4+delta cathode exhibited a higher overpotential with La0.8Sr0.2Ga0.83Mg0.17O2.815 (LSGM) as the electrolyte, presumably due to the interdiffusion of La3+ and Nd3+ ions across the electrolyte/cathode interface and subsequent formation of ion-blocking phases at the interface. La1.2N0.8NiO4+delta, on the other hand, provided La isoactivity across the LSGMjcathode interface and therefore an improved performance with the LSGM electrolyte. Since Nd2-xLaxNiO4+delta contains neither Sr nor Co, as a cathode, it might be compatible with the electrolytes such as yttria-stabilized zirconia without the need of a buffer layer. (c) 2007 Elsevier B.V. All rights reserved.