Manufacturing method of a catalyst for a fuel cell
A manufacturing method of a catalyst may modify a carbon layer structure by using various heat treatment gases such as inert gas (Ar), hydrogen, and carbon monoxide in a carbon layer manufacturing process, thereby optimizing the carbon layer structure according to the purpose of a metal without changing a size of the metal.
1 . A method of manufacturing a catalyst for a fuel cell, the method comprising:
(A) obtaining a component including a support and an active metal supported on the support; and
(B) obtaining a catalyst by heat-treating the component in a gas atmosphere, wherein the gas atmosphere comprises carbon monoxide (CO), and
wherein the catalyst comprises the support, the active metal supported on the support, and a carbon layer coated on a surface of the active metal.
2 . The method of claim 1 , wherein the gas atmosphere is a mixed gas atmosphere further comprising argon.
3 . The method of claim 2 , wherein the mixed gas atmosphere comprises argon and carbon monoxide at a volume ratio in a range of 90:10 to 99:1.
4 . The method of claim 1 , wherein operation (B) comprises:
(B-1) primarily heat-treating the component in the gas atmosphere comprising inert gas, hydrogen (H 2 ), carbon monoxide (CO), or any combination thereof; and
(B-2) secondarily heat-treating the primarily heat-treated component in the gas atmosphere comprising inert gas, hydrogen (H 2 ), carbon monoxide (CO), or any combination thereof,
wherein one or more of the gas atmospheres of operation (B-1) and (B-2) is carbon monoxide.
5 . The method of claim 4 , wherein the gas atmosphere of operation (B-1) is a mixed gas atmosphere of nitrogen and hydrogen, and wherein the gas atmosphere of operation (B-2) is carbon monoxide.
6 . The method of claim 5 , wherein the mixed gas atmosphere of (B-1) comprises nitrogen and hydrogen at a volume ratio in a range of 80:20 to 95:5.
7 . The method of claim 1 , wherein the catalyst has a particle diameter in a range of 3 nm to 5 nm obtained from Scherrer's equation by using a half width of a peak with respect to a plane 220 of an X-ray diffraction spectrum.
8 . The method of claim 1 , wherein the catalyst has an exposed metal surface area (EMSA) in a range of 0.1 m 2 /g pt to 25 m 2 /g pt .
9 . The method of claim 1 , wherein the catalyst has catalyst activity in an oxygen reduction reaction (ORR) in a range of 0.1V to 0.7V based on −1.5 mA/cm 2 geo .
10 . The method of claim 1 , wherein the catalyst has mass activity in a hydrogen oxidation reaction (HOR) in a range of 0.5 mA/cm 2 geo to 2.0 mA/cm 2 geo based on 0.02V.