On a variation of the kinetics of hydrogen oxidation on Ni-BaCe(Y,Gd)O_3 anode for proton ceramic fuel cells

摘要

The electrochemical behaviour of Ni-based anodes for H+ solid oxide fuel cells (SOFCs) with a composition consisting of Ni-BaCe0.89Gd0.1Cu0.01O3-5 and Ni-BaCe0.8Y0.2O3-5 was studied. Ni-BaCe0.8Y0.2O3-5 exhibited poorer performance in comparison with Ni-BaCe0.89Gd0.1Cu0.01O3-5, which was explained by the formation of the BaY2NiO5 phase at the electrode-electrolyte interface during electrode sintering. It was found that the hydrogen oxidation rate on the Ni-BaCe0.89Gd0.1Cu0.01O3-5 anode in the temperature range of 700 -900 degrees C was determined by the rate of the three stages. It was shown that the electrode reaction mechanism did not change in this temperature range. At the temperature of 600 degrees C, the reaction mechanism became more complicated, most likely due to the influence of increased protonic conductivity in the electrolyte. The nature of the probable ratedetermining stages of hydrogen oxidation is suggested.(c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.