(305a) Bi-Metallic Catalysts as Sulfur Tolerant Anodes in Solid Oxide Fuel Cells

The Ni-YSZ catalysts currently used as SOFC anodes are highly susceptible to coking and sulfur poisoning. Very low concentrations of sulfur in the fuel feed causes significant deactivation in catalyst activity and fuel cell performance. The current work examines developing bimetallic catalysts by incorporating Tin and Vanadium to the Ni-YSZ catalysts. A fundamental understanding of the interactions on the catalyst surface under the anodic reaction conditions is necessary in-order to tailor the catalyst formulations. The synergistic effect between the components of the catalyst is explored using several in-situ and ex-situ methods. The effect of catalyst synthesis method on the structure and properties of the materials is examined. The structure-property relations of the catalyst materials as well as effect of poisoning are also characterized using X-ray Photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD). The activity as well as stability of these catalysts in the presence of H₂S is studied with time on stream reaction experiments for the various anode reactions. In-situ Vibrational Spectroscopy is used to understand the nature of surface sites, reaction mechanism as well as the nature of de-activation.