In the present work, the steady-state current-overpotential characteristics of the Fe vertical bar BaCe0.5Zr0.3Y0.08Yb0.08Cu0.04O3-delta vertical bar Fe interface as a function of the gas phase composition and temperature are investigated. To this purpose a BaCe0.5Zr0.3Y0.08Yb0.08Cu0.04O3-delta dense ceramic material is successfully synthesized by solid state synthesis and sintered at 1400 degrees C. Then its crystal structure, ceramic and electrical properties are investigated. It is found that the ceramic has a high relative density (more than 90%) and acceptable proton conductivity (1.5 and 6.8 mS cm(-1) at 500 and 900 degrees C, respectively). On the as prepared BaCe0.5Zr0.3Y0.08Yb0.08Cu0.04O3-delta electrolyte disk, three thin Fe porous layers are deposited by painting on both sides (three electrode system), which is then immersed in a tubular single-chamber continuous electrochemical reactor. The polarization measurements are carried out in the temperature range between 500 and 700 degrees C and at three different H-2/He wet (3% steam) compositions. The apparent anodic and cathodic charge transfer coefficients (Tafel region) are found to be: alpha(a) = alpha(c) = 0.8, while the apparent activation energy is calculated to be approximately 0.55 +/- 0.05 eV. It is also found that by increasing the hydrogen concentration the current density increases, especially at higher temperature values. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.