Catalyst laminate, membrane electrode assembly, electrochemical cell, stack, water electrolyzer, and hydrogen utilizing system

Patent metadata

Field	Value
Publication number	US-11515552-B2
Application number	US-201916293170-A
Country	US
Kind code	B2
Filing date	Mar 5, 2019
Priority date	Mar 22, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A catalyst laminate includes a plurality of catalyst layers containing at least one of a noble metal and an oxide of the noble metal and at least one of a non-noble metal and an oxide of the non-noble metal, including:two or more first catalyst layers and two or more second catalyst layers. In an atomic percent of the noble metal obtained by using a line analysis by energy dispersive X-ray spectroscopy in a thickness direction of the catalyst laminate. The first catalyst layer is less than an average of a highest value and a lowest value of the atomic percent of the noble metal. The second catalyst layer has an atomic percent of the noble metal equal to or greater than the average of the highest value and the lowest value thereof. The second catalyst layer is present between the first catalyst layers.

First claim

What is claimed is:

1. A catalyst laminate comprising a plurality of catalyst layers, comprising:
a first catalyst layer, wherein the first catalyst layer contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide;
a second catalyst layer, wherein the second catalyst layer contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide; and
a third catalyst layer, wherein the third catalyst laver contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide,
wherein, in an atomic percent of the noble metal obtained by using a line analysis by energy dispersive X-ray spectroscopy in a thickness direction of the catalyst laminate,
wherein the first catalyst layer has an atomic percent of the noble metal less than an average of a highest value and a lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the second catalyst layer has an atomic percent of the noble metal equal to or greater than the average of the highest value and the lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the third catalyst layer has an atomic percent of the noble metal less than an average of a highest value and a lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the second catalyst layer is present between the first catalyst layer and third catalyst layer,
wherein, when a value obtained by dividing an atomic percent of the non-noble metal of the first catalyst layer by an atomic fraction of the noble metal of the first catalyst layer and the third catalyst layer is Rm (A1) and a value obtained by dividing the atomic percent of the non-noble metal of the second catalyst layer by the atomic fraction of the noble metal of the second catalyst layer is Rm (A2), Rm (A1)>Rm (A2),
wherein pillars connecting the first catalyst laver and the third catalyst laver are present in the second catalyst layer,
wherein the pillars contain the noble metal contained in the second catalyst layer,
wherein the first catalyst layer, the second catalyst layer, and the third catalyst layer are stacked in this order,
wherein the first catalyst layer is in direct contact with the second catalyst layer,
wherein the third catalyst layer is in direct contact with the second catalyst layer,
wherein a top of the pillars is in direct contact with the first catalyst layer, and
wherein a bottom of the pillars is in direct contact with the third catalyst layer.

2. The catalyst laminate according to claim 1 , wherein the Rm (A1) is 0.1 or more and 1.0 or less, and
wherein the Rm (A2) is 0.01 or more and 0.45 or less.

3. The catalyst laminate according to claim 1 , wherein an average thickness of the first catalyst layer is larger than that of the second catalyst layer.

4. The catalyst laminate according to claim 1 , wherein an average thickness of the first catalyst layer is 4 nm or more and 35 nm or less, and
wherein an average thickness of the second catalyst layer is 2 nm or more and 34 nm or less.

5. The catalyst laminate according to claim 1 , wherein the first catalyst layer comprises a first area, wherein on 30% or more and less than 90% of the first area, no catalyst is present, and
wherein the third catalyst layer comprises a second area, wherein on 30% or more and less than 90% of the second area, no catalyst is present.

6. The catalyst laminate according to claim 1 , wherein the noble metal of the first catalyst layer or its oxide of the first catalyst layer contains one selected from a group including Ir, Pt, Ru, Rh, Os, Pd, and Au and the non-noble metal of the first catalyst laver or its oxide of the first catalyst layer contains one selected from a group including Fe, Co, Ni, Mn, Al, Zn, Ta, W, Hf, Si, Mo, Ti, Zr, Nb, V, Cr, Sn, and Sr,
wherein the noble metal of the second catalyst layer or its oxide of the second catalyst layer contains one selected from a group including Ir, Pt, Ru, Rh, Os, Pd, and Au and the non-noble metal of the second catalyst layer or its oxide of the second catalyst layer contains one selected from a group including Fe, Co, Ni, Mn, Al, Zn, Ta, W, Hf, Si, Mo, Ti, Zr, Nb, V, Cr, Sn, and Sr, and
wherein the noble metal of the third catalyst layer or its oxide of the third catalyst layer contains one selected from a group including Ir, Pt, Ru, Rh, Os, Pd, and Au and the non-noble metal of the third catalyst layer or its oxide of the third catalyst layer contains one selected from a group including Fe, Co, Ni, Mn, Al, Zn, Ta, W, Hf, Si, Mo, Ti, Zr, Nb, V, Cr, Sn, and Sr.

7. The catalyst laminate according to claim 1 , wherein a gap exists between the pillars.

8. A membrane electrode assembly comprising the catalyst laminate according to claim 1 .

9. An electrochemical cell comprising the membrane electrode assembly according to claim 8 .

10. A stack comprising the electrochemical cell according to claim 9 .

11. A water electrolyzer using the stack according to claim 10 .

12. A hydrogen utilizing system comprising the electrochemical cell according to claim 9 .

13. A hydrogen utilizing system comprising the stack according to claim 10 .

14. A hydrogen utilizing system comprising the water electrolyzer according to claim 11 .

15. A catalyst laminate comprising a plurality of catalyst layers, comprising:
a first catalyst layer, wherein the first catalyst layer contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide;
a second catalyst layer, wherein the second catalyst layer contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide; and
a third catalyst layer, wherein the third catalyst layer contains a noble metal or a noble metal oxide and a non-noble metal or a non-noble metal oxide,
wherein, in an atomic percent of the noble metal obtained by using a line analysis by energy dispersive X-ray spectroscopy in a thickness direction of the catalyst laminate,
wherein the first catalyst layer has an atomic percent of the noble metal less than an average of a highest value and a lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the second catalyst layer has an atomic percent of the noble metal equal to or greater than the average of the highest value and the lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the third catalyst layer has an atomic percent of the noble metal less than an average of a highest value and a lowest value of the atomic percent of the noble metal of the catalyst laminate,
wherein the second catalyst layer is present between the first catalyst layer and the third catalyst layer,
wherein, when a value obtained by dividing an atomic percent of the non-noble metal of the first catalyst layer by an atomic fraction of the noble metal of the first catalyst layer and the third catalyst layer is Rm (A1) and a value obtained by dividing the atomic percent of the non-noble metal of the second catalyst layer by the atomic fraction of the noble metal of the second catalyst layer is Rm (A2), Rm (A1)>Rm (A2),
wherein pillars connecting the first catalyst layer and the third catalyst layer are present in the second catalyst layer,
wherein the pillars contain the noble metal contained in the second catalyst layer,
wherein the first catalyst layer, the second catalyst layer, and the third catalyst layer are stacked in this order,
wherein the first catalyst layer is in direct contact with the second catalyst layer,
wherein the third catalyst layer i

Assignees

• Toshiba Kk

Inventors

• Iida Atsuko
• Yoshinaga Norihiro
• Mei Wu
• Nakano Yoshihiko

Classifications

• C23C14/185 Primary

  by cathodic sputtering · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• H01M8/1004 Primary

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

• C23C14/0036

  Reactive sputtering · CPC title

• C25B1/04

  by electrolysis of water · CPC title