Fuel cell electrode and method for producing same

• US 5,277,996 A
• Filed: 07/02/1992
• Issued: 01/11/1994
• Est. Priority Date: 07/02/1992
• Status: Expired due to Fees

• Current Assignee: George A. Marchetti, William R. Loewe
• Original Assignee: George A. Marchetti, William R. Loewe
• Inventors: Marchetti, George A., Loewe, William R.
• Primary Examiner(s): Maples, John S.
• Application Number:
  US07/907,969
• Time in Patent Office: 558 Days
• Field of Search: 429/44, 429/30, 429/40, 429/12
• US Class Current: 429/535
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C23C 14/0605 Carbon
• CPC Class Codes: C23C 14/18 on other inorganic substrates
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 4/96 Carbon-based electrodes
• CPC Class Codes: H01M 8/0612 from carbon-containing material
• 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: Y10S 977/847 Surface modifications, e.g. functionalization, coating
• CPC Class Codes: Y10S 977/948 Energy storage/generating using nanostructure, e.g. fuel cell, battery

Abstract

An improved fuel cell electrode and method for construction is disclosed wherein the electrodes are formed from adjacent layers of a porous substrate material such as carbon, and C₆₀ carbon molecules or fullerenes. The C₆₀ carbon molecules are arranged in face centered cubes and bind platinum atoms interspaced in the interstices of the cubes and on the C₆₀ molecules to form a Pt/C₆₀ layer. Lattices of platinum atoms are anchored to the individual platinum atoms of the Pt/C₆₀ molecular layer to form a catalyst layer only several molecules thick. The resulting platinum atoms of the catalyst layer have a much greater surface area in contact with the electrolyte due to the chaotic surface area of the catalyst layer. The platinum atoms of that layer act as a catalyst for the fuel cell reaction.

Claims

1. A method for producing an improved electrode for use in a fuel cell having a chamber for fuel, a chamber for an oxidant, an electrolyte layer disposed between the fuel chamber and the oxidant chamber, and two electrodes, the first electrode in contact with the fuel and the electrolyte layer and the second electrode in contact with the oxidant and the electrolyte layer, the first and second electrodes having a plurality of adjacent, substantially planar layers, the process comprising the steps of:

providing a substrate layer having a first and second surface, the first surface of the substrate layer being exposed to the fuel or oxidant;

forming a C₆₀ fullerene molecule layer, having a first and second surface, on the second surface of the substrate layer;

implanting platinum atoms onto the second surface of the C₆₀ fullerene molecule layer, thereby forming a platinum layer in contact with the electrolyte layer.

2. The process in accordance with claim 1 where the step of forming a C₆₀ fullerene molecule layer, having a first and second surface, on the second surface of the substrate layer further comprises:

placing carbon C₆₀ fullerene molecules in a quartz crucible;

lowering the quartz crucible into a tungsten coil; and

energizing the tungsten coil to sublime the C₆₀ fullerene molecules to the second surface of the substrate layer.

3. The process in accordance with claim 1 in which platinum atoms are deposited on the C₆₀ fullerene molecule layer by means of electroplating.

4. The process in accordance with claim 1 in which platinum atoms are deposited on the C₆₀ fullerene molecule layer by means of electron beam evaporation.

5. The process in accordance with claim 1 in which platinum atoms are deposited on the C₆₀ fullerene molecule layer by means of sputtering.

6. The process in accordance with claim 1 in which platinum atoms are deposited on the C₆₀ fullerene molecule layer by means of vaporization.

7. The process in accordance with claim 1 in which the step of providing a substrate layer having a first and second surface further comprises perforating the first surface of the substrate layer with tapered channels sufficient to allow communication of the oxidant through the substrate layer to the platinum layer.

8. The process in accordance with claim 1 in which the step of providing a substrate layer having a first and second surface further comprises perforating the first surface of the substrate layer with tapered channels sufficient to allow communication of the fuel through the substrate layer to the platinum layer.