Electrochemical cell electrocatalyst

Patent metadata

Field	Value
Publication number	US-12500246-B2
Application number	US-202217842316-A
Country	US
Kind code	B2
Filing date	Jun 16, 2022
Priority date	Jun 16, 2022
Publication date	Dec 16, 2025
Grant date	Dec 16, 2025

Abstract

An electrocatalyst includes a conglomerate of platinum atoms forming an amorphous nanoparticle structure having at least about 40% of highly undercoordinated surface atoms with fewer than 6 adjacent atoms on its surface; and a passivating crust including catalytically active monoatomic adsorbed oxygen atoms such that at least 50% of the amorphous nanoparticle structure has oxygen coverage, the amorphous nanoparticle structure having a diameter of up to 3 nm.

First claim

What is claimed is:

1 . An electrocatalyst comprising:
a conglomerate of platinum atoms forming an amorphous nanoparticle structure having at least about 40% of highly undercoordinated surface atoms with fewer than 6 adjacent atoms on its surface; and a passivating crust including catalytically active monoatomic adsorbed oxygen atoms such that at least 50% of the amorphous nanoparticle structure has oxygen coverage, the amorphous nanoparticle structure having a diameter of up to 3 nm.

2 . The electrocatalyst of claim 1 , wherein the amorphous nanoparticle structure has a disorderly, irregular surface lacking a clear facet organization.

3 . The electrocatalyst of claim 1 , wherein the amorphous nanoparticle structure includes an amorphized internal structure.

4 . The electrocatalyst of claim 1 , wherein the passivating crust further comprises one or more species of PtO x , where x is 1-3.

5 . The electrocatalyst of claim 4 , wherein a ratio of the monoatomic adsorbed oxygen atoms to the one or more species of PtO x is up to about 3:1.

6 . The electrocatalyst of claim 1 , wherein the electrocatalyst has an internal structure more orderly than an outer surface.

7 . The electrocatalyst of claim 1 , wherein the amorphous nanoparticle structure comprises at least about 50% Pt.

8 . The electrocatalyst of claim 1 , wherein the passivating crust is amorphous.

9 . A cathode catalyst layer comprising:
an electrocatalyst support; an electrocatalyst attached onto the support, the electrocatalyst having
a highly amorphous nanoparticle structure comprising a plurality of inner atoms and surface atoms, the surface atoms comprising at least about 30% atoms with lone pairs having a coordination number of less than 6, based on the total mass of the surface atoms; and
a stable corrosion-resistive layer of adsorbed oxygen species covering at least 50% of the surface atoms.

10 . The cathode catalyst layer of claim 9 , wherein the adsorbed oxygen species include a catalytically active monoatomic oxygen.

11 . The cathode catalyst layer of claim 9 , wherein the adsorbed oxygen species include one or more species of PtO x , where x is 1-3.

12 . The cathode catalyst layer of claim 9 , wherein the highly amorphous nanoparticle structure comprises at least about 50% Pt.

13 . The cathode catalyst layer of claim 9 , wherein the highly amorphous nanoparticle structure has a diameter of up to about 3 nm.

14 . The cathode catalyst layer of claim 9 , wherein more than about 50% of the inner atoms have a coordination number of up to 12.

15 . The cathode catalyst layer of claim 9 , wherein an entire electrocatalyst is non-crystalline.

16 . An electrochemical cell comprising:
an anode; a membrane separating the anode from a cathode; and the cathode including a cathode catalyst layer having an electrocatalyst comprising a plurality of platinum ultra-fine, highly amorphized nanoparticles, each having a diameter of up to about 3 nm and having an amorphous inner core covered with a passivating crust of oxygen species adsorbed onto the surface of the amorphous inner core at more than 50% surface coverage.

17 . The electrochemical cell of claim 16 , wherein the oxygen species include a catalytically active monoatomic oxygen.

18 . The electrochemical cell of claim 16 , wherein the oxygen species are dispersed on the surface of the amorphous inner core in an irregular manner.

19 . The electrochemical cell of claim 16 , wherein the cathode catalyst layer further includes a second Pt electrocatalyst having a diameter greater than 3 nm.

Assignees

• Bosch Gmbh Robert

Inventors

• Gadelrab Karim
• Kornbluth Mordechai
• Kim Soo
• Mailoa Jonathan

Classifications

• H01M8/1004

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• H01M4/92

  Metals of platinum group (H01M4/94 {, H01M4/9058} take precedence) · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M4/921

  Alloys or mixtures with metallic elements · CPC title

• Y02E60/50

  Fuel cells · CPC title