Methods of forming materials containing carbon and boron, methods of forming catalysts, filaments comprising boron and carbon, and catalysts

• US 6,235,675 B1
• Filed: 09/21/1999
• Issued: 05/22/2001
• Est. Priority Date: 09/22/1998
• Status: Expired due to Fees

• Current Assignee: Idaho Research Foundation, Inc.
• Original Assignee: Idaho Research Foundation, Inc.
• Inventors: McIlroy, David N.
• Primary Examiner(s): Wood, Elizabeth D.
• Application Number:
  US09/399,865
• Time in Patent Office: 609 Days
• Field of Search: 502/174, 502/177, 502/527.16, 502/527.14, 502/527.24, 501/95.1, 501/87, 423/291, 428/368, 428/367, 428/366, 428/378, 428/392, 428/688, 428/704, 427/255.2, 427/249
• US Class Current: 502/177
• CPC Class Codes: B01J 21/02 Boron or aluminium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 27/20 Carbon compounds
• CPC Class Codes: B01J 27/22 Carbides
• CPC Class Codes: B01J 35/58 Fabrics or filaments
• CPC Class Codes: B01J 37/0238 via the gaseous phase-sublimation
• CPC Class Codes: B01J 37/349 making use of flames, plasmas or lasers
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01B 32/991 Boron carbide
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/10 extending in one dimension, e.g. needle-like
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C23C 16/32 Carbides
• CPC Class Codes: Y10S 977/734 Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
• CPC Class Codes: Y10S 977/762 Nanowire or quantum wire, i.e. axially elongated structure having two dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/773 Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/775 Nanosized powder or flake, e.g. nanosized catalyst
• CPC Class Codes: Y10S 977/788 Of specified organic or carbon-based composition
• CPC Class Codes: Y10S 977/843 : Gas phase catalytic growth, i.e. chemical vapor deposition
• CPC Class Codes: Y10S 977/89 : Deposition of materials, e.g. coating, cvd, or ald
• CPC Class Codes: Y10T 428/2916 : including boron or compound thereof [not as steel]
• CPC Class Codes: Y10T 428/2918 : including free carbon or carbide or therewith [not as steel]
• CPC Class Codes: Y10T 428/292 : In coating or impregnation
• CPC Class Codes: Y10T 428/2938 : Coating on discrete and individual rods, strands or filaments
• CPC Class Codes: Y10T 428/2964 : Artificial fiber or filament

Abstract

In one aspect, the invention includes a method of forming a material containing carbon and boron, comprising: a) providing a substrate within a chemical vapor deposition chamber; b) flowing a carbon and boron precursor into the chamber, the precursor being a compound that comprises both carbon and boron; and c) utilizing the precursor to chemical vapor deposit a material onto the substrate, the material comprising carbon and boron. In another aspect, the invention includes a method of forming a catalyst, comprising: a) providing a substrate within a chemical vapor deposition chamber; b) flowing a carbon and boron precursor into the chamber, the precursor being a compound that comprises both carbon and boron; c) utilizing the precursor to chemical vapor deposit a first material onto the substrate, the first material comprising carbon and boron; and d) coating the first material with a catalytic material. In yet another aspect, the invention includes a material comprising: a) a plurality of individual filaments, the individual filaments comprising boron and carbon; and b) greater than 90% of the individual filaments having a thickness of less than 150 nanometers.

Claims

1. A method of forming a material containing carbon and boron, comprising:

providing a substrate within a chemical vapor deposition chamber;

flowing a carbon and boron precursor into the chamber, the precursor being a compound that comprises both carbon and boron; and

utilizing the precursor to chemical vapor deposit a material onto the substrate, the material comprising carbon and boron.

2. The method of claim 1 wherein the utilizing comprises subjecting the precursor to plasma enhanced chemical vapor deposition conditions.

3. The method of claim 1 wherein the chemical vapor deposited material comprises B₄C.

4. The method of claim 1 further comprising providing a seed material within the chemical vapor deposition chamber prior to the utilizing.

5. The method of claim 4 wherein the seed material comprises one or more of Fe, Ni and Pt.

6. The method of claim 4 wherein the seed material comprises Fe and is provided to a concentration of greater than 0 and less than about 10 ppm.

7. The method of claim 4 wherein the seed material comprises Fe and is provided to a concentration of greater than 0 and less than about 1 ppm.

8. The method of claim 1 wherein the precursor comprises closo-1,2-dicarbadodecaborane.

9. The method of claim 1 wherein the precursor consists essentially of closo-1,2-dicarbadodecaborane.

10. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments.

11. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of less than 150 nanometers.

12. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of less than 150 nanometers and lengths of at least 13 micrometers.

13. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 150 nanometers.

14. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 150 nanometers and lengths of at least 13 micrometers.

15. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 30 nanometers.

16. The method of claim 1 wherein the chemical vapor deposited material comprises a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 30 nanometers and lengths of at least 13 micrometers.

17. The method of claim 1 wherein the substrate comprises monocrystalline silicon.

18. A method of forming a material containing carbon and boron, comprising:

providing a substrate within a chemical vapor deposition chamber;

flowing carbon and boron precursors into the chamber, the carbon and boron precursors comprising one or more compounds that comprise both carbon and boron; and

subjecting the precursors to plasma-enhanced chemical vapor deposition to deposit a material onto the substrate, the material comprising carbon and boron.

19. The method of claim 18 wherein the carbon and boron precursors comprise closo-1,2-dicarbadodecaborane.

20. The method of claim 18 wherein the carbon and boron precursors consist essentially of closo-1,2-dicarbadodecaborane.

21. The method of claim 18 wherein the material is deposited as a plurality of filaments.

22. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of less than 150 nanometers.

23. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of less than 150 nanometers and lengths of at least 13 micrometers.

24. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 150 nanometers.

25. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 150 nanometers and lengths of at least 13 micrometers.

26. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 30 nanometers.

27. The method of claim 18 wherein the material is deposited as a plurality of filaments, and wherein greater than 90% of the deposited filaments have a thickness of from about 15 nanometers to about 30 nanometers and lengths of at least 13 micrometers.

28. The method of claim 18 wherein the substrate comprises monocrystalline silicon.

29. A method of forming a catalyst, comprising:

providing a substrate within a chemical vapor deposition chamber;

flowing a carbon and boron precursor into the chamber, the precursor being a compound that comprises both carbon and boron;

utilizing the precursor to chemical vapor deposit a first material onto the substrate, the first material comprising carbon and boron; and

coating the first material with a catalytic material.

30. The method of claim 29 wherein the catalytic material comprises platinum.

31. The method of claim 29 wherein the catalytic material comprises platinum and wherein the coating comprises:

flowing dimethyl (1,5 cyclooctadiene) platinum into the chamber; and

subjecting the dimethyl (1,5 cyclooctadiene) platinum to plasma enhanced chemical vapor deposition conditions.

32. A method of forming a catalyst, comprising:

providing a substrate within a chemical vapor deposition chamber;

flowing carbon and boron precursors into the chamber;

subjecting the precursors to plasma-enhanced chemical vapor deposition to deposit a first material onto the substrate, the first material comprising carbon and boron; and

coating the first material with a catalytic material.

33. The method of claim 32 wherein the catalytic material comprises platinum.

34. The method of claim 32 wherein the catalytic material comprises platinum and wherein the coating comprises:

flowing dimethyl (1,5 cyclooctadiene) platinum into the chamber; and

subjecting the dimethyl (1,5 cyclooctadiene) platinum to plasma enhanced chemical vapor deposition conditions.

35. A filament comprising:

a thickness of less than 150 nanometers; and

boron and carbon essentially throughout the thickness.

36. The filament of claim 35 wherein the boron and carbon are in the form of B₄C.

37. The filament of claim 35 comprising a cylindrical shape having smoothly curved side surfaces.

38. The filament of claim 35 comprising a cylindrical shape having smoothly curved side surfaces, the cylinder having a cross-sectional diameter of from about 15 nanometers to about 30 nanometers.

39. The filament of claim 35 comprising a cylindrical shape having faceted side surfaces.

40. The filament of claim 35 comprising a cylindrical shape having faceted side surfaces, the cylinder having a cross-sectional width of from about 25 nanometers to about 75 nanometers.

41. The filament of claim 35 being shaped as a linear array of one or more cylinders terminating at one or more rhomboidal nodes.

42. The filament of claim 35 comprising a length of at least 13 micrometers.

43. The filament of claim 35 having a thickness of from 18 nanometers to 150 nanometers.

44. The filament of claim 35 having a thickness of from 15 nanometers to 30 nanometers.

45. A material comprising:

a plurality of individual filaments,

greater than 90% of the individual filaments having a thickness of less than 150 nanometers;

the individual filaments comprising boron and carbon throughout substantially all of the thickness.

46. The material of claim 45 wherein greater than 90% of the filaments have lengths of at least 13 micrometers.

47. The material of claim 45 having an aspect ratio of from about 90 to about 720.

48. The material of claim 45 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 150 nanometers.

49. The material of claim 45 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 150 nanometers and lengths of at least 13 micrometers.

50. The material of claim 45 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 30 nanometers.

51. The material of claim 45 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 30 nanometers and lengths of at least 13 micrometers.

52. A catalytic material comprising:

a support structure comprising a plurality of individual filaments, the individual filaments comprising boron and carbon, greater than 90% of the individual filaments having a thickness of less than 150 nanometers; and

a catalytic coating on the individual filaments, the catalytic coating comprising a material that catalyzes oxidation of CO and hydrocarbons.

53. The material of claim 52 wherein the catalytic material comprises platinum.

54. The material of claim 52 wherein greater than 90% of the filaments have lengths of at least 13 micrometers.

55. The material of claim 52 having an aspect ratio of from about 90 to about 720.

56. The material of claim 52 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 150 nanometers.

57. The material of claim 52 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 150 nanometers and lengths of at least 13 micrometers.

58. The material of claim 52 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 30 nanometers.

59. The material of claim 52 wherein greater than 90% of the filaments have thicknesses of from about 15 nanometers to about 30 nanometers and lengths of at least 13 micrometers.