(569a) NiMo-Ceria-Zirconia-Based Internal Reforming Solid Oxide Fuel Cell
In this talk, we present an application of a NiMo-ceria-zirconia (NiMo-CZ) catalyst as an internal reforming unit for solid oxide fuel cells (SOFCs) running on a model gasoline fuel. Solid oxide fuel cells (SOFCs) are a promising energy conversion device because they can efficiently and directly convert the chemical energy of fuels into electrical energy. Nickel-based anodes are commonly used in SOFCs due to their low cost, good chemical stability, and excellent catalytic activity toward hydrogen oxidation and reforming of small hydrocarbon molecules. However, the Ni-based anodes are well known for promoting severe surface carbon deposition. Excessive formation of carbon species on the anode leads to a rapid deterioration of the cell performance by physically blocking access of the reactants to the active catalyst sites. Recently, our group successfully synthesized a NiMo-ceria-zirconia catalyst that displayed not only high reforming activity for various liquid hydrocarbons, but also excellent coking tolerance. In this presentation, we show how the NiMo-ceria-zirconia catalyst are integrated as an internal reforming unit into conventional (1) Ni-YSZ anode supported single cell and (2) tubular cell designs. Effects of the internal reforming system on electrochemical performance of the SOFCs were comparatively investigated by running the cells with an isooctane/air mixture as fuel. After the electrochemical performance measurement, the anodes were characterized using various analytical techniques including X-ray diffraction (XRD), and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX). Effects of the internal reforming unit on electrochemical performance and performance stability of the SOFCs were also investigated.