Method of electrodepositing a porous film

• US 6,503,382 B1
• Filed: 03/20/2000
• Issued: 01/07/2003
• Est. Priority Date: 06/27/1997
• Status: Expired due to Fees

• Current Assignee: University of Southampton
• Original Assignee: University of Southampton
• Inventors: Bartlett, Philip Nigel, Attard, George Simon, Elliott, Joanne, Owen, John Robert
• Primary Examiner(s): Nguyen, Nam
• Assistant Examiner(s): Leader, William T.
• Application Number:
  US09/446,725
• Time in Patent Office: 1,023 Days
• Field of Search: 205/50, 205/67, 205/75, 205/102, 205/112, 205/220, 204/483, 204/489, 204/490, 428/315.5, 428/613
• US Class Current: 205/67
• CPC Class Codes: C25D 3/02 from solutions C25D5/34 - C25D5/46 take precedence
• CPC Class Codes: C25D 9/00 Electrolytic coating other than with metals C25D11/00, C25D15/00 take precedence; electrophoretic coating C25D13/00

Abstract

A method of preparing a porous film comprises electrodepositing material from a mixture onto a substrate, the mixture comprising: (I) a source of metal, inorganic oxide, non-oxide semiconductor/conductor or organic polymer, (II) a solvent such as water; and (III) a structure-directing agent such as octaethylene glycol monododecyl ether in an amount sufficient to form an homogeneous lyotropic liquid crystalline phase in the mixture. Electrodepositing the film from a lyotropic liquid phase in this manner provides a porous film having a substantially regular structure and substantially uniform pore size. Following deposition, the porous film may be treated to remove the structure-directing agent. The porous film may optionally be subjected to further treatment such as the electrochemical or chemical insertion of ionic species, the physical absorption of organic, inorganic or organometallic species, or the electrodeposition, solution phase deposition or gas phase deposition of organic, inorganic or organometallic species.

Claims

1. A method of preparing a porous film which comprises electrodepositing material from a mixture onto a substrate to form a porous film, wherein the mixture comprises:

a source of metal, inorganic oxide, non-oxide semiconductor/conductor or organic polymer, or a combination thereof;

a solvent; and

a structure-directing agent in an amount sufficient to form an homogeneous lyotropic liquid crystalline phase in the mixture, and optionally removing the structure-directing agent.

2. A method according to claim 1 wherein the mixture comprises a lyotropic liquid crystalline phase exhibiting a hexagonal or cubic topology.

3. A method according to claim 1 wherein the mixture comprises a source of a metal selected from the group consisting of platinum, palladium, gold, nickel, cobalt, copper, chromium, indium, tin and lead.

4. A method according to claim 1 wherein the mixture comprises a source of an oxide of a metal selected from the group consisting of titanium, vanadium, tungsten, manganese, nickel, lead and tin.

5. A method according to claim 1 wherein the mixture comprises a source of a non-oxide semiconductor or conductor selected from the group consisting of germanium, silicon, selenium, gallium arsenide, indium stibnate, indium phosphide, cadmium sulphide and metal hexacyanometallates.

6. A method according to claim 1 wherein the mixture comprises a source of an organic polymer selected from the group consisting of polyaniline, polypyrrole, polythiophene, polyphenol, polyacrylonitrile, poly(ortho-phenylene diamine) and derivatives thereof.

7. A method according to claim 1 wherein the solvent is water.

8. A method according to claim 1 wherein the structure-directing agent is octaethylene glycol monododecyl ether or octaethylene glycol monohexadecyl ether.

9. A method according to claim 1 wherein the structure-directing agent is present in the mixture in an amount of at least 20% by weight based on the total weight of the solvent and structure-directing agent.

10. A method according to claim 1 wherein the mixture further comprises a hydrophobic hydrocarbon additive to control the pore diameter and/or regular structure of the deposited film.

11. A method according to claim 10 wherein the hydrocarbon is present in the mixture in a molar ratio to the structure-directing agent in the range of 0.5 to 1.

12. A method according to claim 1 wherein an electrodeposition potential is varied to deposit the material sequentially into layers.

13. A method according to claim 1 wherein the structure-directing agent is present in the mixture in an amount of at least 30% by weight based on the total weight of the solvent and structure-directing agent.