Enhanced methane electrooxidation by ceria and nickel oxide impregnated perovskite anodes in solid oxide fuel cells

Abstract

A key challenge preventing the full utilization of the electrochemical work potentials of hydrocarbon fuels in solid oxide fuel cells (SOFCs) is the prevalence of partial hydrocarbon electrooxidation at the anode and the resultant catalytic deactivation by coking. CeO2-NiO impregnated La-0.3 Sr0.5TiO3-delta (LSTA ) anodes solve both issues. These anodes exhibit 2-fold increase in the exchange current density (i(o)) for CH4 electrooxidation compared to CeO2 impregnated NiO-YSZ (yttria-stabilized-zirconia) anodes. The presence of metal support interactions between Ni-CeO2-delta along with the oxygen vacancies in LSTA- and CeO2-delta- enabled fast oxidation of carbon species and resulted in reduced coking. The uses of this anode in an electrolyte supported full cell configuration yielded a maximum power density of 490 mW cm(-2) in CH4 at 1173 K. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.