Discharge driven gold catalyst with application to a CO.sub.2 laser

• US 4,756,000 A
• Filed: 02/18/1987
• Issued: 07/05/1988
• Est. Priority Date: 02/18/1987
• Status: Expired due to Term

• Current Assignee: John A. Macken
• Original Assignee: John A. Macken
• Inventors: Macken, John A.
• Primary Examiner(s): Scott, Jr., Leon
• Application Number:
  US07/016,061
• Time in Patent Office: 503 Days
• Field of Search: 372/59, 372/87, 372/83, 372/89, 372/55, 372/61, 372/92, 372/34, 378/98, 378/58, 378/81
• US Class Current: 372/59
• CPC Class Codes: H01S 3/036 Means for obtaining or maintaining the desired gas pressure within the tube, e.g. by gettering, replenishing; Means for circulating the gas, e.g. for equalising the pressure within the tube H01S3/031 takes precedence

Abstract

A device and process using a gold as a catalyst for oxidizing carbon monoxide to form CO₂ at ambient temperatures. This has particular application to CO₂ lasers. In one CO₂ laser embodiment, gold is distributed on the walls of the discharge volume. The gold is divided to form electrically isolated islands to prevent interference with the discharge. Energetic forms of oxygen, such as atomic oxygen reacts with CO on the gold catalyst. In another embodiment, the gold catalyst is used in a convective flow laser.

Claims

1. A CO₂ laser device including a closed envelope containing a CO₂ laser gas mixture and laser amplification volume, said amplification volume including an electrical discharge through said CO₂ laser gas mixture, said discharge causing decomposition of CO₂ in said mixture to form carbon monoxide, oxygen, and energetic forms of oxygen, the improved feature comprising:

inside said envelope there is at least one surface coated with gold;

said gold surface is positioned and configured as to promote contact with both said carbon monoxide and said energetic forms of oxygen generated in said amplification volume for purposes of catalizing formation of CO₂.

2. The combination according to claim 1 wherein the said gold catalyst is on at least a portion of the wall area facing said amplification volume, said gold is distributed over a sufficiently broad area of said well area so as to promote the catalytic formation of CO₂ in at least a substantial portion of said laser gas mixture in said amplification volume.

3. The combination according to claim 2 where said gold catalyst is supported by a dielectric material and where said gold catalyst forms multiple, generally microscopic regions which are electrically insulated from each other.

4. The combination according to claim 2 where said gold catalyst has been divided into multiple, generally macroscopic, regions which are electrically insulated from each other.

5. The combination according to claim 1 wherein said gold catalyst and said electrode are different.

6. The combination according to claim 5 wherein the said gold catalyst functions independently as part of a laser resonator reflector.

7. The combination according to claim 1 wherein said CO₂ laser device has said gas mixture rapidly flowing through said amplification volume and where said gold coated surface is a relatively large surface area structure designed to make intimate contact with said flowing gas and positioned sufficiently close to the gas exhaust end of said amplification volume to be contacted by a substantial amount of said energetic oxygen. Further, in operation, said gold catalyzes the formation of CO₂ to the extent that there is a substantial reduction in the total molecular oxygen in the amplification volume compared to the oxygen content without said gold coating.

8. In a method for converting carbon monoxide and oxygen to CO₂ the steps in no particular order comprising:

provide a means for forming at least one energetic form of oxygen;

provide a gold coated surface positioned so as to promote contact with both said carbon monoxide and said energetic form of oxygen for the purposes of making catalytic formation of CO₂.

9. The method of claim 8 where the step of providing a means for forming at least one energetic form of oxygen includes the step of providing energy to a source of oxygen, said energy means selected from the group consisting of:

an electrical discharge, electromagnetic radiation shorter than 3000 Angstroms wavelength, or rapidly moving subatomic particles.

10. The method of claim 9 where the step of providing an energy source includes providing an electric discharge in a CO₂ laser device.

11. The method of claim 8 where the step of providing a gold coated surface includes supporting said gold surface with a dielectric material and also dividing said gold surface in such a way as to form multiple electrically insulated islands of gold.