The performance of PtCo/C catalysts in the presence of a metal oxides layer for an oxygen reduction reaction (ORR) was investigated. Different types of metal oxides (CeO2, MoO2 and TiO2) and metal loadings (0.03-0.45 mg/cm(2)) were incorporated on the PtCo/C catalyst layer. Their activity was analyzed in acid solution and proton exchange membrane (PEM) fuel cell under a H-2/O-2 environment at 60 degrees C and ambient pressure, while the stability was tested in an N-2-saturated H2SO4 solution using repetitive potential cycling. It was found that the addition of metal oxides on a catalyst layer had no influence for PtCo/C morphology. However, they significantly affected the electrochemical surface area (ESA), internal contact resistance (ICR) and hydrophilic/hydrophobic properties of the catalysts layer. Furthermore, they significantly affected the ORR activity and stability in acid solution and PEM fuel cell operation. Among all studied metal oxides, the TiO2 exhibited the best property for use as the catalyst interlayer in PEM fuel cell for both activity and stability enhancement. (C) 2016 Elsevier Ltd. All rights reserved.