Method of preparing a catalyst for a fuel cell without a carbon support

Patent metadata

Field	Value
Publication number	US-11081703-B2
Application number	US-201916394468-A
Country	US
Kind code	B2
Filing date	Apr 25, 2019
Priority date	Dec 20, 2018
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

A method of preparing a catalyst for a fuel cell includes no carbon support. The method of preparing a catalyst for a fuel cell includes preparing a first metal nanoparticle having a polyhedral shape, growing a second metal along the edge of the first metal nanoparticle, and removing the first metal nanoparticle.

First claim

What is claimed is:

1. A method of preparing a catalyst for a fuel cell, the method comprising:
preparing a first metal nanoparticle;
growing a second metal along an edge of the first metal nanoparticle; and
removing the first metal nanoparticle,
wherein the growing the second metal comprises precipitating a trace of a third metal on a surface of the first metal nanoparticle and replacing the third metal precipitated on the edge of the first metal nanoparticle with the second metal.

2. The method of claim 1 , wherein the first metal is selected from the group consisting of Au, Cu, Co, and combinations thereof.

3. The method of claim 1 , wherein the first metal nanoparticle has an average particle size of 40 nm to 70 nm.

4. The method of claim 1 , wherein the second metal is selected from the group consisting of Pt, Rh, Ru, and combinations thereof.

5. The method of claim 1 , wherein the second metal site-selectively grows along the edge of the first metal nanoparticle.

6. The method of claim 1 , wherein the third metal is selected from the group consisting of Ag, Cu, Ni, and combinations thereof.

7. The method of claim 1 , wherein the third metal is replaced with the second metal through a galvanic replacement reaction.

8. The method of claim 1 , wherein the first metal nanoparticle has a polyhedral shape, and wherein the second metal grows along the edge of the first metal nanoparticle to form a frame having a same shape as the polyhedral shape of the first metal nanoparticle.

9. The method of claim 1 , wherein the removing the first metal nanoparticle comprises etching the first metal nanoparticle in a solution using an etching agent.

10. The method of claim 8 , wherein the first metal nanoparticle is removed so that the first metal is left behind on an inner surface of the frame of the second metal in a form of a thin film.

11. A method of preparing a catalyst layer for a fuel cell, the method comprising:
dropping a droplet comprising a catalyst, which has been prepared using the method of claim 1 , onto a substrate; and
evaporating the droplet.

12. The method of claim 11 , wherein the evaporating the droplet is performed at a temperature of 30° C. to 70° C.

13. The method of claim 11 , wherein the catalyst is self-assembled as the droplet is evaporated.

14. The method of claim 11 , wherein the catalyst layer has a thickness of 2 μm to 12 μm.

15. A method of preparing a catalyst layer for a fuel cell, the method comprising:
preparing a catalyst for a fuel cell by preparing a first metal nanoparticle, growing a second metal along an edge of the first metal nanoparticle, and removing the first metal nanoparticle;
dropping a droplet comprising the catalyst onto a substrate; and
evaporating the droplet,
wherein the catalyst is self-assembled as the droplet is evaporated.

16. The method of claim 15 , wherein the evaporating the droplet is performed at a temperature of 30° C. to 70° C.

17. A method of preparing a catalyst layer for a fuel cell, the method comprising:
preparing a catalyst for a fuel cell by preparing a first metal nanoparticle, growing a second metal along an edge of the first metal nanoparticle, and removing the first metal nanoparticle;
dropping a droplet comprising the catalyst onto a substrate; and
evaporating the droplet,
wherein the catalyst layer has a thickness of 2 μm to 12 μm.

18. The method of claim 17 , wherein the evaporating the droplet is performed at a temperature of 30° C. to 70° C.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp
• Research & Business Found Sungkyunkwan Univ

Inventors

• Park Ju Ahn
• Park Sung Ho

Classifications

• H01M4/8842

  Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor · CPC title

• H01M8/086

  Phosphoric acid fuel cells [PAFC] · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• H01M4/8853

  Electrodeposition · CPC title