Methods for forming electrocatalyst structures and electrodes comprising same

Patent metadata

Field	Value
Publication number	US-11316169-B2
Application number	US-201916439277-A
Country	US
Kind code	B2
Filing date	Jun 12, 2019
Priority date	Jun 12, 2018
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

Described herein are methods of forming an electrocatalyst structure on an electrode, comprising depositing a first layer on the electrode using atomic layer deposition (ALD), wherein the first layer comprises a plurality of discrete nanoparticles of a first electrocatalyst, and depositing one or more of a second layer on the first layer and the electrode using ALD, wherein the one or more second layer comprises a second electrocatalyst, wherein the first layer and the one or more second layers, collectively, form a multi-layer electrocatalyst structure on the electrode. Also described are electrodes having a multi-layer electrocatalyst structure. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

First claim

What is claimed is:

1. A method of forming an electrocatalyst structure on an electrode, comprising:
depositing a first layer on the electrode using atomic layer deposition (ALD), wherein the first layer comprises a plurality of discrete nanoparticles of a first electrocatalyst; and
depositing one or more of a second layer on the first layer and the electrode using ALD, wherein the each of the one or more second layers independently comprises a second electrocatalyst; and
wherein the first layer and the one or more second layers collectively form a deposited electrocatalyst structure on the electrode;
subjecting the electrode to electrochemical operation at a temperature equal to or greater than about 650° C., thereby transforming deposited electrocatalyst structure to an operated electrocatalyst structure.

2. The method of claim 1 , wherein the first electrocatalyst comprises a noble metal.

3. The method of claim 2 , wherein the first electrocatalyst comprises platinum (Pt).

4. The method of claim 1 , wherein the discrete nanoparticles of the deposited electrocatalyst structure have an average particle size of less than about 200 nanometers in the largest dimension.

5. The method of claim 1 , wherein the second electrocatalyst comprises an electronically conducting material that has catalytic activity for ORR.

6. The method of claim 1 , wherein the second electrocatalyst comprises a metal oxide comprising one or more transition metals.

7. The method of claim 1 , wherein the second electrocatalyst comprises a metal oxide comprising manganese, cobalt, or both, having the formula (Mn 1-y Co y ) 3 O 4 , wherein y has a value from 0.0 to 1.0.

8. The method of claim 1 , wherein each of the one or more second layers of the deposited electrocatalyst structure, independently, has a thickness of from about 1 nanometers to about 200 nanometers.

9. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in a plurality of pores or fissures extending through a thickness of the second layer.

10. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in the formation of a plurality of discrete nanograins of the second electrocatalyst separated by intergranular grain boundaries.

11. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in the formation of a plurality of triple phase boundaries at intergranular grain boundaries.

12. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in at least a portion of the plurality of the nanoparticles of the first electrocatalyst populating adjacent one or more of triple phase boundaries at intergranular grain boundaries.

13. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in the formation of a plurality of coupled grains comprising one of the plurality of nanoparticles of the first electrocatalyst, and a nanograin of the second electrocatalyst.

14. The method of claim 1 , wherein the subjecting the electrode to electrochemical operation results in the formation of a plurality of core-shell nanostructures, each core-shell nanostructure comprising a core comprising a nanoparticle of the first electrocatalyst, that is at least partially covered by a shell comprising the second electrocatalyst.

Assignees

• Univ West Virginia

Inventors

• Song Xueyan
• Chen Yun
• Gerdes Kirk

Classifications

• Y02E60/50

  Fuel cells · CPC title

• C23C16/18 Primary

  from metallo-organic compounds · CPC title

• H01M4/8867

  Vapour deposition · CPC title

• H01M4/8657 Primary

  layered · CPC title

• C23C16/45555

  applied in non-semiconductor technology · CPC title