NiMo-Ceria-Zirconia Catalyst for Inert-Substrate-Supported Tubular Solid Oxide Fuel Cells Running on Model Gasoline

Abstract

A novel NiMo-ceria-zirconia catalyst was developed for an inert-substrate-supported tubular single cell running on isooctane fuel. The catalyst with composition of 11 wt.% Ni, 3 wt.% Mo and 86 wt.% ceria-zirconia showed high activity for reforming of isooctane/air mixture and excellent coking tolerance. This catalyst was applied in the tubular single cell consisted of an inert porous yttira-stabilized zirconia (YSZ) supporter, Ni-Ce0.8Sm0.2O1.9 (Ni-SDC) anode, YSZ/SDC bilayer electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. By packing the catalyst into the tubular channel of the single cell, the mixture of isooctane and air can be efficiently reformed to simple syngas (a mixture of hydrogen and carbon monoxide) at 750 °C. The carbon conversion reached 75% and the hydrogen and carbon monoxide yields were over 50%, which were much higher compared with the cell with no catalyst (carbon conversion: <50%, syngas yields: <35%). As a result, the maximum initial power density of the single cell increased from 240 to 306 mW cm-2 by applying the catalyst. Moreover, the single cell displayed significantly improved stability during the 18 h performance test. The results suggest the feasibility of applying the NiMo-ceria-zirconia catalyst for operating the tubular single cell using isooctane fuel.