Catalytic CeO2 washcoat over microchanneled supporting cathodes of solid oxide electrolysis cells for efficient and stable CO2 reduction

Abstract

Infiltration is an effective way to improve porous electrode performance of solid oxide cells while the preparation procedure and catalyst stability still remain challenging. The microchannel structure of cathodes enables the implementation of catalysts into conventional Ni-based cathode supports of solid oxide electrolysis cells via the infiltration process to accelerate CO2 electrolysis. Infiltrating a CeO2 colloid precursor to prepare catalytic washcoat has been demonstrated as a more efficient catalyst preparation and resulted in a more stable CO2 electrolysis performance, compared with infiltrating conventional nitrate precursors. The catalytic CeO2 washcoat possesses a uniform particle size distribution and strong adhesion to the cathode scaffold surface. The optimization of the infiltration process results in a remarkable stability of CO2 electrolysis performance during cell operation for 334 h owing to the stable catalyst microstructure.