This work presents the effect of dispersed copper oxide (CuO) nanoparticles on the oxygen reduction reaction (ORR) on a typical solid oxide fuel cell (SOFC) electrocatalyst, La0.6Sr0.4Co0.2Fe0.8O3-delta(LSCF). The ORR kinetics were enhanced by a factor up to 4 at 750 degrees C as demonstrated by electrical conductivity relaxation measurements used to determine the chemical surface exchange coefficient, k(chem). The value of k(chem) increased from 2.6 x 10(-5) cm s(-1) to 9.3 x 10(-5) cm s(-1) at 750 degrees C when the LSCF surface was coated with submicron CuO particles. The enhanced k(chem) was attributed to additional reactions that occur on the CuO surface and at the LSCF-CuO-gas three-phase boundaries (3PBs) as suggested by the k(chem) dependence on CuO coverage and 3PB length. This enhancement was further demonstrated by the introduction of CuO nanoparticles into LSCF electrodes. CuO infiltrated electrodes reduced the interfacial polarization resistance from 2.27 Omega cm(2) to 1.5 Omega cm(2) at 600 degrees C and increased the peak power density from 0.54 W cm(-2) to 0.72 W cm(-2) at 650 degrees C. Electrochemical impedance spectroscopy indicated that the reduced resistance was due to the shrinkage of the low frequency arc, which is associated with the electrochemical surface exchange reaction. (C) 2016 Elsevier B.V. All rights reserved.