Electrocatalysts comprising transition metals and chalcogen for oxygen evolution reactions (OER) and manufacturing thereof

Patent metadata

Field	Value
Publication number	US-12234157-B2
Application number	US-202017109948-A
Country	US
Kind code	B2
Filing date	Dec 2, 2020
Priority date	Dec 3, 2019
Publication date	Feb 25, 2025
Grant date	Feb 25, 2025

Abstract

The present description relates to metal alloy electrocatalysts, preferably composed of Ni and Co as transition metals and Se as a chalcogen. The electrocatalysts can take the form of nanochalcogenides that can be made using cryogenic milling followed by surfactant-assistant milling. The electrocatalysts can be used in the context of water electrolysis or electroreduction of CO 2 gas into carbon based products.

First claim

The invention claimed is:

1. A process for producing a nanochalcogenide for use in electrocatalysis, comprising:
subjecting at least two transition metals and at least one chalcogen to cryogenic milling to produce an alloyed chalcogenide material;
subjecting the alloyed chalcogenide material to surfactant-assisted milling to produce a slurry comprising a nanochalcogenide; and
separating the nanochalcogenide from the slurry,
wherein the surfactant-assisted milling comprises surfactant-assisted ball milling performed in the presence of at least one surfactant and a solvent; and
wherein the solvent comprises an alcohol and the least one surfactant comprises diphenylphosphoryl acid (DPPA), or oleic acid, or CTAB surfactant.

2. The process of claim 1 , wherein the cryogenic milling comprises cryogenic ball milling.

3. The process of claim 2 , wherein the cryogenic milling comprises linear vibrational milling performed at speeds of 25 Hz to 35 Hz.

4. The process of claim 2 , wherein the cryogenic ball milling is performed at a ball-to-powder ratio (BPR) of 8:1 to 12:1 on a mass basis.

5. The process of claim 1 , wherein the alloyed chalcogenide material produced by cryogenic milling comprises particles having an average size above 1000 nm, measured using DLS or SEM.

6. The process of claim 1 , wherein the alloyed chalcogenide material produced by cryogenic milling comprises M 1 M 2 E and/or (M 1 M 2 ) 3 E 4 , wherein M 1 is a first transition metal, M 2 is a second transition metal and E is a chalcogen, and is a single phase.

7. The process of claim 1 , wherein the least one surfactant is present in an amount of 1:3 to 1:5 surfactant-to-powder ratio on a mass basis with respect to the mass of the alloyed chalcogenide material.

8. The process of claim 1 , wherein the surfactant-assisted milling is performed at a ball-to-powder ratio (BPR) of 30:1 to 70:1 on a mass basis.

9. The process of claim 1 , wherein the surfactant-assisted milling is performed to produce the nanochalcogenide in the form of chalcogenide nanoparticles.

10. The process of claim 9 , wherein the surfactant-assisted milling produces the slurry comprising the chalcogenide nanoparticles and a milling liquid, and the separating comprises centrifuging, and wherein the chalcogenide nanoparticles separated by centrifuging have an average size smaller than 100 nm, measured using DLS or SEM.

11. The process of claim 10 , wherein the centrifuging comprises a first centrifuging stage to remove larger particles followed by a second centrifuging stage to remove at least a portion of the chalcogenide nanoparticles.

12. The process of claim 1 , further comprising sonicating the slurry prior to the separating.

13. The process of claim 1 , wherein the at least two transition metals are selected from Ni, Co, and Fe.

14. The process of claim 1 , wherein the at least two transition metals are Ni and Co.

15. The process of claim 14 , wherein the at least one chalcogen is Se.

16. The process of claim 1 , further comprising activating the separated nanochalcogenide to produce an activated electrocatalyst, wherein the activating comprises:
selectively etching the at least one chalcogen out of the nanochalcogenide, leaching the at least one chalcogen out of the nanochalcogenide, or transforming the at least two transition metals into active oxyhydroxides thereof.

17. The process of claim 1 , wherein the at least two transition metals and the at least one chalcogen are atomically dispersed in the nanochalcogenide, and wherein the nanochalcogenide has an average particle size less than 100 nm, measured using DLS or SEM, and wherein the at least two transition metals comprise Ni and Co, and the chalcogen comprises Se.

18. The process of claim 1 , wherein the at least one chalcogen comprises Se.

19. The process of claim 18 , wherein the at least two transition metals comprise Ni and Co.

20. A process for producing a nanochalcogenide for use in electrocatalysis, comprising:
subjecting at least two transition metals and at least one chalcogen to a first milling stage to produce an alloyed chalcogenide material having an average particle size above 1 micrometer and a disordered structure including amorphous and nanocrystalline structures;
subjecting the alloyed chalcogenide material to a second milling stage to produce a slurry comprising nanochalcogenides having a particle size below 100 nm, measured using DLS or SEM; and
separating the nanochalcogenides from the slurry,
wherein:
the second milling stage comprises surfactant-assisted milling that comprises surfactant-assisted ball milling performed in the presence of at least one surfactant and a solvent; and the solvent comprises an alcohol and the least one surfactant comprises diphenylphosphoryl acid (DPPA), or oleic acid, or CTAB surfactant;
the second milling stage comprises surfactant-assisted milling that comprises surfactant-assisted ball milling performed in the presence of at least one surfactant and a solvent; and wherein the surfactant-assisted milling is performed at a ball-to-powder ratio (BPR) of 30:1 to 70:1 on a mass basis; or
the first milling stage comprises cryogenic ball milling and wherein: the cryogenic ball milling comprises linear vibrational milling performed at speeds of 25 Hz to 35 Hz, or the cryogenic ball milling is performed at a ball-to-powder ratio (BPR) of 8:1 to 12:1 on a mass basis.

21. A process for producing a nanochalcogenide for use in electrocatalysis, comprising:
subjecting at least two transition metals and at least one chalcogen to cryogenic milling to produce an alloyed chalcogenide material;
subjecting the alloyed chalcogenide material to surfactant-assisted milling to produce a slurry comprising a nanochalcogenide; and
separating the nanochalcogenide from the slurry;
wherein the surfactant-assisted milling comprises surfactant-assisted ball milling performed in the presence of at least one surfactant and a solvent; and wherein the surfactant-assisted milling is performed at a ball-to-powder ratio (BPR) of 30:1 to 70:1 on a mass basis.

22. A process for producing a nanochalcogenide for use in electrocatalysis, comprising:
subjecting at least two transition metals and at least one chalcogen to cryogenic milling to produce an alloyed chalcogenide material;
subjecting the alloyed chalcogenide material to surfactant-assisted milling to produce a slurry comprising a nanochalcogenide; and
separating the nanochalcogenide from the slurry;
wherein the cryogenic milling comprises cryogenic ball milling; and
wherein:
the cryogenic milling comprises linear vibrational milling performed at speeds of 25 Hz to 35 Hz; or
the cryogenic ball milling is performed at a ball-to-powder ratio (BPR) of 8:1 to 12:1 on a mass basis.

Assignees

• Governing Council Univ Toronto
• Totalenergies Onetech

Inventors

• Abed Jehad
• Thorpe Steven
• Sargent Edward

Classifications

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• H01M4/9041

  Metals or alloys (H01M4/92 takes precedence) · CPC title

• C01B19/002

  Compounds containing, besides selenium or tellurium, more than one other element, with -O- and -OH not being considered as anions · CPC title

• C25B3/26

  of carbon dioxide · CPC title

• C25B11/091

  consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds · CPC title