Electrocatalyst for water electrolysis

Patent metadata

Field	Value
Publication number	US-12163236-B2
Application number	US-202317803894-A
Country	US
Kind code	B2
Filing date	Jan 12, 2023
Priority date	Oct 4, 2018
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A cathode is provided for electrolysis of water wherein the cathode material comprises a multi-principal element, transition metal dichalcogenide material that has four or more chemical elements and that is a single phase, solid solution. The pristine cathode material does not contain platinum as a principal (major) component. However, a cathode comprising a transition metal dichalcogenide having platinum (Pt) nanosized islands or precipitates disposed thereon is also provided.

First claim

We claim:

1. A composite electrode comprising an electrode material and a conductive material, wherein the electrode material comprises a single, solid solution phase consisting of a transition metal chalcogen phase devoid of a non-transition metal chalcogen phase, represented by the general formula of:
(M a 1 M b 2 M c 3 . . . . M n )(X 1 A X 2 B X 3 C ),
wherein M 1 , M 2 , M 3 . . . M n each represents a different transition metal and wherein at least three transition metals are present and the sum of a+b+c . . . n is between 1 and 3, wherein X 1 , X 2 , X 3 each represents a chalcogen element selected from the group consisting of S, Se, and Te and wherein the sum of A+B+C is between 2 and 6 and wherein the material does not contain platinum as a principal (major) component and wherein the composite electrode comprises a mixture of (a) particles of the transition metal chalcogen phase and (b) particles of the conductive material disposed on a substrate and wherein the composite electrode exhibits an overpotential below 0.5 V vs the reversible hydrogen electrode (HRE) at 10 mA/cm 2 current density during electrolysis of water in acidic environment at room temperature.

2. The composite electrode of claim 1 wherein the conductive material comprises particulates of one or more of graphite, graphene, graphene oxide, reduced graphene oxide, metal, polymer, and ceramic that show overpotential below 0.5 V vs the reversible hydrogen electrode (HRE) at 10 mA/cm 2 current density during electrolysis of water in acidic environment at room temperature.

3. The composite electrode of claim 1 that is stable in acidic aqueous environment.

4. The composite electrode of claim 1 wherein the electrode material comprises three group 4 and/or group 5 transition metals, and/or group 6 transition metal, and/or group 9 transition metal, and/or group 10 transition metal.

5. The composite electrode of claim 1 wherein the electrode material contains Ta as a transition metal.

6. The composite electrode of claim 1 wherein the electrode material comprises at least one of
(W 0.4 Mo 0.4 Ta 0.2 ) S2 , (W 0.475 Mo 0.475 Ta 0.05 ) S2 , (Mo 0.475 W 0.475 Ta 0.05 )SSe and (Mo 0.4 W 0.4 Ta 0.2 )SSe.

7. The composite electrode of claim 1 wherein the electrode material comprises particles of the size between 0.6 nm and 5 micron (5000 nm) in at least one dimension.

8. The composite electrode of claim 7 wherein the electrode material comprises particles of the size between 0.6 nm and 5 micron (5000 nm) in one dimension and more than 1 micron in the second and/or third dimensions wherein the particles include at least one of nano plates, micro plates, rods, wires, tubes, and thin films.

9. The composite electrode of claim 1 wherein the electrode material contains at least three transition metals selected from the group Cr, Mo, W, Ta, Nb, V, Hf, Zr, Pd, and Pt.

10. The composite electrode of claim 1 wherein the electrode material comprises a single, solid solution phase consisting of a transition metal chalcogen phase devoid of a non-transition metal chalcogen phase, represented by the general formula of:
(M a 1 M b 2 M c 3 . . . . M n )(X 1 A X 2 B X 3 C ),
wherein M 1 , M 2 , M 3 . . . . M n each represents a different transition metal and wherein at least three transition metals are present and the sum of a+b+c . . . n is between 1 and 3, wherein X 1 , X 2 , X 3 each represents a chalcogen element selected from the group consisting of S as X 1 A , Se as X 2 B , and Te as X 3 C wherein the chalcogen element includes S alone or S and at least one of Se and Te and wherein the sum of A+B+C is between 2 and 6 with the proviso that Se is present only together with S as A+B=2, and wherein the material does not contain platinum as a principal (major) component and that exhibits a stable overpotential during water electrolysis at room temperature.

11. The composite electrode of claim 10 wherein the transition metal chalcogen phase includes Ta as a transition metal.

12. A water electrolysis cell, comprising an anode, a cathode, and a power source, wherein the cathode comprises the composite electrode of claim 1 .

Assignees

• Univ Iowa State Res Found Inc

Inventors

• Balema Viktor
• Padalkar Sonal
• Hlova Ihor
• Lan Tian
• Dolotko Oleksandr
• Pecharsky Vitalij K
• Johnson Duane D
• Pathak Arjun K
• Singh Prashant

Classifications

• 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

• C25B11/057

  consisting of a single element or compound · CPC title

• C25B11/051

  Electrodes formed of electrocatalysts on a substrate or carrier · CPC title

• C25D13/02

  with inorganic material · CPC title

• C23C18/1639

  Substrates other than metallic, e.g. inorganic or organic or non-conductive · CPC title