Examination of Morphological and Chemical Properties of Ni-BZY Anodes and their Influence upon Methane Reactivity and Electrochemical Performance of Protonic-Ceramic Fuel Cells

Ni-BZY (yttrium-doped barium zirconate) has drawn recent interest for application in protonic ceramic fuel cells (PCFCs) due to BZY’s superior protonic conductivity and stability in reforming environments containing CO 2 and H 2 O. Additionally, Ni and BZY form unique nano/microstructures thought to synergistically facilitate reforming. While PCFCs with Ni-BZY anodes have demonstrated stable long-term performance, little is known about the material’s transformations during operation and subsequent impact on electrochemical metrics. To address this knowledge gap, we constructed PCFCs consisting of Ni-BZY anodes sintered onto a ~600 μm BZY electrolyte complete with a LSCF/BCZY cathode. The electrochemical performance of these cells is compared at 600-700 °C while operating with humidified hydrogen, neat methane, and steam reformed methane (1CH 4 :1H 2 O). Insights into morphological and chemical changes are provided by pre- and post-mortem analysis of the anode via Raman spectroscopy, X-ray diffraction, and SEM. Phase transformations, agglomeration and coking all appeared to contribute to performance degradation.