Precursor of Pr2NiO4+δ as a highly effective catalyst for the simultaneous promotion of oxygen reduction and hydrogen oxidation reactions in solid oxide electrochemical devices

The electrochemical behaviour of a Sr2Fe1.5Mo0.5O6-5 based double-layer electrode decorated with a symmetric catalyst by the wet impregnation technique for the simultaneous acceleration of cathodic and anodic reactions was investigated for the first time. As a symmetric catalyst, a solution of precursor for the synthesis of praseodymium nickelate (Pr2NiO4+5) was considered. Since the catalyst consists of NiO and Pr6O11 in an oxidizing atmosphere and of Ni and Pr2O3 in a reducing atmosphere, it effectively accelerates the rate of oxygen reduction at the cathode and hydrogen oxidation at the anode of solid oxide fuel cells with symmetric electrodes. It was shown that the rate of oxygen reduction after introduction of the catalyst into the electrode increased due to an increase in the rate of oxygen interfacial exchange between the electrode and the gas phase. The rate of hydrogen oxidation increased due to an increase in the rate of dissociation of adsorbed hydrogen. During tests of the fuel cell with a 300 mm LaGaO3-based supporting electrolyte and decorated electrodes, a maximum power density of about 0.83 W cm-2 at 800 degrees C under wet hydrogen/air condition was obtained. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The electrochemical behavior of a Sr2Fe1.5Mo0.5O6-5-based double-layer electrode decorated with a symmetric catalyst by the wet impregnation technique for the simultaneous acceleration of cathodic and anodic reactions was investigated for the first time. The introduction of the symmetric catalyst effectively accelerated the rate of oxygen reduction at the cathode and hydrogen oxidation at the anode of solid oxide fuel cells with symmetric electrodes, leading to an increased power density at 800 degrees C under wet hydrogen/air condition.