Microstructure, Mechanical Behavior and Catalytic Activity of NiO-ZrO2 Anode Composite

Abstract

Long-term operation of the solid oxide fuel cell (SOFC) depends strongly on reliability of its components. In the case of SOFCs incorporating Ni-ScCeSZ anodes, hydrogen reduction of Ni results in changes in the chemistry, microstructure and properties of the Ni-ZrO2 anode material. In this work, the influence of microstructure of non-reduced (NiO-ScCeSZ) and reduced (Ni-ScCeSZ) anodes on their strength were studied. It was found considerable deterioration in mechanical behavior of Ni-ScCeSZ anodes after reduction comparing to initial state. Biaxial strength of anode samples decrease from ~100 MPa in air at ambient temperature to ~20 MPa after reduction in hydrogen atmosphere at 600°C. Reduced anode samples were used for studying its catalytic activity for conversion of methane into CO. The degradation of anode structures during reduction decreases its catalytic activity.