Metallization of bacterial cellulose for electrical and electronic device manufacture

• US 7,955,759 B2
• Filed: 09/23/2010
• Issued: 06/07/2011
• Est. Priority Date: 12/14/2001
• Status: Expired due to Fees

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Evans, Barbara R., O'Neill, Hugh M., Woodward, Jonathan, Jansen, Valerie Malyvanh
• Primary Examiner(s): Alejandro; Raymond
• Application Number:
  US12/889,155
• Publication Number:
  US 20110014525A1
• Time in Patent Office: 257 Days
• Field of Search: 429/535, 429/523, 429/524, 429/401, 429/7, 502/101, 502/300, 502/326
• US Class Current: 429/535
• CPC Class Codes: H01M 4/8605 Porous electrodes
• CPC Class Codes: H01M 4/8817 Treatment of supports before application of the catalytic active composition coated porous composites H01M8/0245
• CPC Class Codes: H01M 4/8842 Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor
• CPC Class Codes: H01M 4/92 Metals of platinum group H01M4/94 , H01M4/9058 take precedence
• CPC Class Codes: H01M 4/96 Carbon-based electrodes
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method for the deposition of metals in bacterial cellulose and for the employment of the metallized bacterial cellulose in the construction of fuel cells and other electronic devices is disclosed. The method for impregnating bacterial cellulose with a metal comprises placing a bacterial cellulose matrix in a solution of a metal salt such that the metal salt is reduced to metallic form and the metal precipitates in or on the matrix. The method for the construction of a fuel cell comprises placing a hydrated bacterial cellulose support structure in a solution of a metal salt such that the metal precipitates in or on the support structure, inserting contact wires into two pieces of the metal impregnated support structure, placing the two pieces of metal impregnated support structure on opposite sides of a layer of hydrated bacterial cellulose, and dehydrating the three layer structure to create a fuel cell.

Claims

1. A method for forming a fuel cell, the method comprising:

providing an electrode support structure comprising bacterial cellulose;

placing the electrode support structure in a solution of a metal salt for a sufficient time period such that the metal salt is reduced to metallic form and the metal precipitates in or on the electrode support structure to form an electrode material;

providing an electrolyte membrane;

placing an anode on one side of the electrolyte membrane; and

placing a cathode on an opposite side of the electrolyte membrane,

wherein one of the anode and the cathode comprises the electrode material, and

wherein the electrode support structure comprises hydrated bacterial cellulose, and

wherein the method further comprises dehydrating the electrode support structure after the metal precipitates in or on the electrode support structure to form the electrode material, and

wherein the metal salt is selected from coordination compounds including a platinum metal group complex ion, and mixtures thereof.

2. The method of claim 1 wherein:

the anode comprises the electrode material and the cathode comprises the electrode material.

3. The method of claim 1 wherein:

the electrolyte membrane comprises bacterial cellulose.

4. The method of claim 1 wherein:

the electrolyte membrane comprises hydrated bacterial cellulose,

the anode comprises the electrode material,

the cathode comprises the electrode material, and

the method further comprises dehydrating the electrolyte membrane, the anode and the cathode after placing the anode on one side of the electrolyte membrane and placing the cathode on the opposite side of the electrolyte membrane thereby affixing the anode and the cathode to the electrolyte membrane.

5. The method of claim 1 wherein:

the electrolyte membrane comprises hydrated bacterial cellulose,

the anode comprises the electrode material,

the cathode comprises the electrode material, and

the method further comprises dehydrating the electrolyte membrane after placing the anode on one side of the electrolyte membrane and placing the cathode on the opposite side of the electrolyte membrane thereby affixing the anode and the cathode to the electrolyte membrane.

6. The method of claim 1 wherein the method further comprises contacting the electrode support structure with a reductant fluid when the electrode support structure is placed in the solution of the metal salt.

7. The method of claim 1 wherein the electrolyte membrane comprises bacterial cellulose and a sulfonated polymer.