Catalyst for oxidizing carbon monoxide for reformer used in fuel cell, method of preparing same, and fuel cell system including same

A method of preparing a carbon monoxide oxidizing catalyst for a reformer of a fuel cell system, comprising the steps of:

• mixing one of alumina and cordierite with a cerium compound solution;
• adding the mixture to a transition element compound solution;
• subjecting the mixture, including said one of alumina and cordierite, the cerium compound, and the transition element compound, to a first calcination to form a calcinated product;
• adding a Cu compound solution to the calcinated product to form a mixture;
• and
• subjecting the mixture to a second calcination.

A fuel cell system, comprising:

• a reformer which includes a reforming reaction part which generates hydrogen gas from a fuel through a catalyst reforming reaction using heat energy, and a carbon monoxide reducing part which reduces carbon monoxide concentration in the hydrogen gas through an oxidation reaction of the hydrogen gas with oxygen;
• at least one electricity generating element for generating electrical energy by electrochemical reactions of the hydrogen gas and oxygen;
• a fuel supplier for supplying the fuel to the reforming reaction part;
• an oxidant supplier for supplying an oxidant to the carbon monoxide reducing part and said at least one electricity generating element, respectively;
• and
• a cooler for cooling heat generated by the carbon monoxide reducing part by circulating the fuel supplied to the reforming reaction part to the carbon monoxide reducing part;
• wherein the reformer further comprises a carrier selected from the group consisting of alumina, cordierite, and combinations thereof, and an active material including CeO2, MO, and CuO, where M is a transition element which is supported on the carrier.