Metal / Metal Chalcogenide Electrode With High Specific Surface Area

Patent metadata

Field	Value
Publication number	US-2019119822-A1
Application number	US-201716096740-A
Country	US
Kind code	A1
Filing date	Mar 31, 2017
Priority date	Apr 27, 2016
Publication date	Apr 25, 2019
Grant date	—

Abstract

The present invention relates to an electrode comprising an electrically conductive substrate of which at least one portion of the surface is covered with a metal deposit of copper, the surface of said deposit being in an oxidised, sulphurised, selenised and/or tellurised form and the deposit having a specific surface area of more than 1 m 2 /g; a method for preparing such an electrode; and a method for oxygenising water with dioxygen involving such an electrode.

First claim

1 . An electrode comprising an electrically conductive substrate of which at least one part of the surface is covered with a copper metal deposit, the surface of said deposit being in an oxidized, sulphurized, selenized and/or tellurized form and the deposit having a specific surface area greater than or equal to 1 m 2 /g.

2 . The electrode according to claim 1 , wherein the electrically conductive substrate consists, at least in part, of an electrically conductive material selected from a metal; a metal oxide; a metal sulphide; carbon; a semiconductor; and a mixture thereof.

3 . The electrode according to claim 1 , wherein the metal deposit has a thickness comprised between 10 μm and 2 mm.

4 . The electrode according to claim 1 , wherein the metal deposit has a specific surface area comprised between 1 m 2 /g and 500 m 2 /g.

5 . The electrode according to claim 1 , wherein the metal deposit has a porous structure with an average pore size comprised between 10 μm and 500 μm.

6 . The electrode according to claim 1 , wherein the surface of the metal deposit is in an oxidized and/or sulphurized form.

7 . A process for preparing an electrode according to claim 1 comprising the following successive steps:
(i) electrodeposition of copper on at least one part of the surface of an electrically conductive substrate so as to form a metal deposit of said copper on said at least one part of the surface of the electrically conductive substrate, and
(ii) oxidation, sulphurization, selenization and/or tellurization of the surface of the metal deposit.

8 . The process according to claim 7 , wherein step (i) is carried out according to the following successive steps:
(a) at least partial immersion of the electrically conductive substrate in an acidic aqueous solution containing ions of the copper to be deposited, and (b) application of a current between the electrically conductive substrate and a second electrode.

9 . The process according to claim 8 , wherein the acidic aqueous solution containing ions of the copper to be deposited is an acidic aqueous solution containing a water-soluble salt of the copper to be deposited.

10 . The process according to claim 8 , wherein the current of step (b) has a current density comprised between 0.1 mA/cm 2 and 5 A/cm 2 .

11 . The process according to claim 7 , wherein step (ii) comprises:
an oxidation, sulphurization, selenization and/or tellurization step carried out at a temperature comprised between 30 and 700° C., wherein the oxidation step is carried out in an atmosphere containing dioxygen or in the presence of H 2 O, the sulphurization step is carried out in the presence of elemental sulphur or H 2 S, the selenization step is carried out in the presence of elemental selenium or H 2 Se, and the tellurization step is carried out in the presence of elemental tellurium or H 2 Te, and optionally an annealing step carried out at a temperature comprised between 50° C. and 1000° C.

12 . The process according to claim 7 , wherein step (ii) is followed by a step (iii) carried out according to the following successive steps:
(1) immersion at least of the part of the electrically conductive substrate covered with a metal deposit the outer surface of which is oxidized, sulphurized, selenized and/or tellurized obtained in step (ii) in a solution containing copper ions, and (2) application of a potential between the electrically conductive substrate and a second electrode, the electric potential applied to the electrically conductive substrate being negative then positive, wherein step (iii) may be repeated once or several times.

13 . An electrode obtainable by a process according to claim 7 .

14 . An electrochemical device comprising an electrode according to claim 1 .

15 . The electrochemical device according to claim 14 , being an electrolysis device or a fuel cell.

16 . A process for oxidizing water to dioxygen comprising the application of an electric current between an anode and a cathode, the anode being an electrode according to claim 1 immersed in water or in a fluid containing water.

17 . The electrode according to claim 2 , wherein the metal is copper, steel, aluminium, or zinc; the metal oxide is fluorine-doped tin oxide (FTO) or indium tin oxide (ITO); the metal sulphide is cadmium sulphide or zinc sulphide; the carbon is in the form of carbon felt, graphite, vitreous carbon, or boron-doped diamond; and the semiconductor is silicon.

18 . The electrode according to claim 4 , wherein the metal deposit has a specific surface area comprised between 3 m 2 /g and 50 m 2 /g.

19 . The electrode according to claim 5 , wherein the metal deposit has a porous structure with an average pore size comprised between 30 μm and 70 μm.

20 . The process according to claim 9 , wherein the water-soluble salt of the copper to be deposited is selected from CuSO 4 , CuCl 2 , Cu(ClO 4 ) 2 , and a mixture thereof.

Assignees

• Paris Sciences Lettres Quartier Latin
• Centre Nat Rech Scient
• Univ Sorbonne

Inventors

• Fontecave Marc
• Mougel Victor
• Tran Ngoc Huan

Classifications

• H01M4/8853

  Electrodeposition · CPC title

• C25D3/38

  of copper · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• H01M4/9016

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• C25D5/48

  After-treatment of electroplated surfaces · CPC title