Robust platinum-copper catalysts

Patent metadata

Field	Value
Publication number	US-9502716-B2
Application number	US-201314084053-A
Country	US
Kind code	B2
Filing date	Nov 19, 2013
Priority date	Nov 19, 2012
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

Highly active and stable platinum-copper (PtCu) electrocatalysts are provided. The PtCu catalysts can be in the form of discrete, spherical PtCu nanoparticles that include a particle interior comprising platinum and copper, and a surface layer comprising platinum surrounding the particle interior. The PtCu nanoparticles can exhibit enhanced oxygen reduction reaction (ORR) activity as compared to other Pt-based catalysts for ORR. The PtCu nanoparticles are also active as electrocatalysts for the oxidation of small molecule organic compounds, including alcohols such as methanol and ethanol.

First claim

What is claimed is:

1. A population of platinum-copper (PtCu) nanoparticles comprising a
(a) a particle interior comprising platinum and copper; and
(b) a surface layer comprising platinum surrounding the particle interior,
wherein the nanoparticles have an average particle size of from 60 nm to 500 nm, as determined by scanning electron microscopy (SEM).

2. The nanoparticles of claim 1 , wherein the population of nanoparticles is monodisperse.

3. The nanoparticles of claim 1 , wherein the molar ratio of Pt:Cu in the nanoparticles is from 0.5:1 to 3:1, as determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS).

4. The nanoparticles of claim 1 , wherein the nanoparticles exhibit a Pt electrochemical surface area of at least 10 m 2 Pt/g Pt.

5. The nanoparticles of claim 1 , wherein the nanoparticles exhibit an O 2 reduction ICP-MS-determined, internal resistance-corrected (IR-corrected), mass activity at 0.9 V RHE of at least 0.2 A/mg Pt, measured at 25° C. and 100 kPa 02 in 0.1 M HClO 4 .

6. The nanoparticles of claim 1 , wherein the nanoparticles exhibit an O 2 reduction Pt-surface area-based, IR-corrected, specific activity at 0.9 V RHE of at least 750 μA/cm 2 Pt, measured at 25° C. and 100 kPa O 2 in 0.1 M HClO 4 .

7. The nanoparticles of claim 1 , wherein the nanoparticles exhibit less than a 30% reduction in Pt electrochemical surface area following 10,000 cycles between a potential of 0.6 and 1.1 V RHE in O 2 -saturated 0.1 M HClO 4 at 25° C.

8. The nanoparticles of claim 1 , wherein the nanoparticles exhibit less than a 50% reduction in O 2 reduction ICP-MS-determined, IR-corrected, mass activity at 0.9 V RHE , measured at 25° C. and 100 kPa O 2 , following 10,000 cycles between a potential of 0.6 and 1.1 V RHE in O 2 -saturated 0.1 M HClO 4 at 25° C.

9. An electrode comprising the nanoparticles defined by claim 1 disposed on a conductive substrate.

10. The electrode of claim 9 , further comprising a carbonaceous support.

11. A fuel cell comprising an anode, a cathode, and an electrolyte membrane disposed between the anode and the cathode, wherein at least one of the anode and the cathode comprises an electrode defined by claim 9 .

12. A metal-air battery comprising a metal or metal-containing anode, a cathode, and an electrolyte dispose between the anode and the cathode, wherein the cathode comprises an electrode defined by claim 9 .

Assignees

• Ohio State Innovation Foundation

Inventors

• Co Anne
• Coleman Eric

Classifications

• H01M4/926

  on carbon or graphite · CPC title

• Y02E60/50

  Fuel cells · CPC title

• H01M4/8657 Primary

  layered · CPC title

• H01M12/08

  composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type · CPC title

• H01M4/921

  Alloys or mixtures with metallic elements · CPC title