Catalyst for fuel cells and methods of preparing the same

Patent metadata

Field	Value
Publication number	US-12431509-B2
Application number	US-202218058979-A
Country	US
Kind code	B2
Filing date	Nov 28, 2022
Priority date	Nov 18, 2022
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

The present disclosure provides a catalyst for urea oxidation reaction, a method of preparing the same, and a use thereof. The catalyst for urea oxidation reaction includes transition metal oxides forming on a metal substrate, and the transition metals includes Fe, Co, and Ni. The method for preparing the catalyst includes contacting the metal substrate with a homogeneous solution to obtain the catalyst for urea oxidation reaction, and the homogeneous solution includes transition metal nitrate precursors and a sulfur precursor. The method of the present application is a low-cost, high-efficiency, and simple process that can be mass produced.

First claim

What is claimed is:

1. A method for preparing a urea oxidation catalyst, comprising contacting a metal substrate with a homogeneous solution for performing a metal corrosion reaction to obtain the urea oxidation catalyst, wherein the homogeneous solution comprises transition metal nitrate precursors and a sulfur precursor dissolved therein, wherein the urea oxidation catalyst comprises a sulfur-doped transition metal hydroxide formed on the metal substrate, and wherein the transition metal hydroxide is represented by MNZ(OH) x , the M, N and Z are iron, cobalt, and nickel, respectively, and x is a positive integer of 1 to 3.

2. The method according to claim 1 , wherein the sulfur-doped transition metal hydroxide is uniformly formed on the metal substrate, and the metal substrate is a porous metal substrate.

3. The method according to claim 2 , wherein the sulfur-doped transition metal hydroxide formed on the metal substrate includes a structure of nanoparticles.

4. The method according to claim 1 , wherein the porous metal substrate is a nickel foam.

5. The method according to claim 1 , wherein the transition metal nitrate precursors and the sulfur precursor are dissolved in water, ethanol, isopropanol, or any combination thereof.

6. The method according to claim 1 , wherein the transition metal nitrate precursors include a nickel nitrate precursor, a ferric nitrate precursor and a cobalt nitrate precursor, and wherein the contents of the nickel nitrate precursor, the ferric nitrate precursor and the cobalt nitrate precursor are equimolar.

7. The method according to claim 1 , wherein the urea oxidation catalyst comprises 25 to 30 element % of the nickel, 0.8 to 1.5 element % of the iron, 0.2 to 0.7 element % of the cobalt, 5 to 10 element % of the sulfur, and 55 to 70 element % of the O based on the total amount of the sulfur, M, N, Z, and O.

8. The method according to claim 1 , wherein the sulfur precursor includes one selected from the group consisting of thiourea, sodium thiosulphate, sodium sulfide, and a combination thereof.

9. The method according to claim 1 , which is carried out at room temperature.

10. The method according to claim 1 , which is performed without applying voltage or current.

11. A urea oxidation catalyst, comprising a sulfur-doped transition metal hydroxide and a metal substrate, wherein the transition metal hydroxide is represented by MNZ(OH) x , the M, N and Z are iron, cobalt, and nickel, respectively, and x is a positive integer of 1 to 3, and wherein the sulfur-doped transition metal hydroxide is disposed on the metal substrate.

12. The urea oxidation catalyst according to claim 11 , wherein the metal substrate is a porous metal substrate.

13. The urea oxidation catalyst according to claim 12 , wherein the porous metal substrate is a nickel foam.

14. The urea oxidation catalyst according to claim 11 , wherein the urea oxidation catalyst comprises 25 to 30 element % of the nickel, 0.8 to 1.5 element % of the iron, 0.2 to 0.7 element % of the cobalt, 5 to 10 element % of the sulfur and 55 to 70 element % of the O based on the total amount of the sulfur, M, N, Z, and O.

15. The urea oxidation catalyst according to claim 11 , wherein the sulfur-doped transition metal hydroxide includes a structure of nanoparticles.

16. An use of the urea oxidation catalyst according to claim 11 , comprising applying the oxidation catalyst in a hydrogen fuel cell.

Assignees

• Univ Nat Cheng Kung

Inventors

• Ting Jyh-Ming
• Wei zi-yun

Classifications

• H01M4/8621

  containing only metallic or ceramic material, e.g. made by sintering or sputtering · CPC title

• H01M4/8803

  Supports for the deposition of the catalytic active composition (H01M4/90 takes precedence) · CPC title

• H01M4/8825

  Methods for deposition of the catalytic active composition · CPC title

• H01M4/9075 Primary

  Catalytic material supported on carriers, e.g. powder carriers (H01M4/8807, H01M4/881, H01M4/8814, H01M4/925 take precedence) · CPC title

• H01M4/9016 Primary

  Oxides, hydroxides or oxygenated metallic salts · CPC title