Nano carbon materials for enhancing thermal transfer in fluids

• US 20020100578A1
• Filed: 01/29/2002
• Published: 08/01/2002
• Est. Priority Date: 01/30/2001
• Status: Active Grant

• Current Assignee: Materials and Electrochemical Research Corporation
• Original Assignee: Materials and Electrochemical Research Corporation
• Inventors: Withers, James C., Loutfy, Raouf O.
• Granted Patent: US 6,695,974 B2
• Time in Patent Office: Days
• US Class Current: 165/80.4
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 32/15 Nano-sized carbon materials
• CPC Class Codes: C01B 32/156 After-treatment
• CPC Class Codes: C09K 5/10 Liquid materials
• CPC Class Codes: Y10S 977/833 Thermal property of nanomaterial, e.g. thermally conducting/insulating or exhibiting peltier or seebeck effect

Abstract

A novel fluid heat transfer agent suitable for use in a closed heat transfer system, for example, wherein energy is transferred between an evaporator and a condenser in heat exchange relationship with the heat transfer agent that is caused to flow from one to the other. The novel heat transfer agent is a complex comprising a body of heat transfer fluid, for example, ethylene glycol or water, having suspended therein carbon nanoparticles in a quantity sufficient to enhance the thermal conductivity of the body of heat transfers fluid, per se. The carbon nanoparticles are selected from carbon in the form of sp² type and sp³ type bonding and preferably comprise nanotubes or fullerenes and may have a coupling agent bonded thereto or enclosed therein when the nanotube or fullerene forms a hollow capsule. The coupling agent may be a polar organic group covalently bonded to the carbon nanoparticles and miscible in the fluid medium.

Claims

1. A fluid complex suitable for use as a heat transfer agent comprising a body of heat transfer fluid having suspended therein carbon nanoparticles comprised of carbon selected from carbon in the forms of sp² type bonding and sp³ type bonding in a quantity sufficient to enhance the thermal conductivity of said fluid, as compared to the thermal conductivity of said heat transfer fluid per se.

3. The fluid complex of claim 1, wherein the carbon nanoparticles consist essentially of nanotubes.

4. The fluid complex of claim 1, wherein the carbon nanoparticles consist essentially of diamonds.

5. The fluid complex of claim 4, further includes a suspending agent in the form of Triton X-100.

6. The fluid complex of claim 3 wherein the carbon nanoparticles consist essentially of multiwalled nanotubes having the original growth iron catalyst ball attached to, at least, one end thereof.

7. The fluid complex of claim 1, wherein the nanoparticles consist essentially of fullerenes.

8. The fluid complex of claim 7, wherein the fullerenes are comprised essentially of fullerenes in the form of fullerene epoxide.

9. The fluid complex of claim 8, wherein the carbon nanoparticles consist essentially of fullerene-O—

CH₂—

CH(CH₃)OH.

10. The fluid complex of claim 8, wherein the body of heat transfers fluid comprises water in which the fullerene epoxide is soluble.

11. The fluid complex of claim 9, wherein the body of heat transfer fluid comprises water in which the fullerene-O—

CH<sub>2—

CH(CH3</sub>)is soluble.

12. The fluid complex of claim 3, wherein the carbon nanoparticles consist essentially of single walled nanotubes.

13. The fluid complexes of claim 3, wherein the carbon nanoparticles consist essentially of double walled nanotubes.

14. The fluid complex of claim 13, wherein the double walled nanotubes consist essentially of nanotube-O—

CH₂CH₂CH₂OH.

15. The fluid complex of claim 3, wherein the body of heat transfers fluid comprises ethylene glycol.

16. The fluid complex of claim 14, wherein the body of heat transfers fluid comprises ethylene glycol.

17. The fluid complex of claim 1, wherein the carbon nanoparticles comprise capsule structures having encapsulated therein-another element.

18. The fluid complex of claim 17, wherein the encapsulated element is selected from among:

Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Mo, Ta, Au, Th, La, Ce, Pr, Nb, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Mo, Pd, Sn, W and alloys of any of these elements.

19. The fluid complex of claim 17, wherein the encapsulated element is present as a compound of such element.

20. The fluid complex of claim 18, wherein the encapsulated element is present as a compound of such element.

21. The fluid complex of claim 17, wherein the capsule structures comprises a fullerene.

22. The fluid complex of claim 18, wherein the capsule structures comprises a fullerene.

23. The fluid complex of claim 19, wherein the capsule structures comprises a fullerene.

24. The fluid complex of claims 21, wherein the capsule structure comprises a fullerene in the form of a buckeyball.

25. The fluid complex of claims 22, wherein the capsule structure comprises a fullerene in the form of a buckeyball.

26. The fluid complex of claims 21, wherein the capsule structure comprises a fullerene in the form of a buckeyball.

27. The fluid complex of claims 17, wherein the capsule structure comprises a nanotube.

28. The fluid complex of claims 18, wherein the capsule structure comprises a nanotube.

29. The fluid complex of claims 19, wherein the capsule structure comprises a nanotube.

30. The fluid complex of claim 7, wherein the fullerene comprises cobalt endohedral fullerene.

31. The fluid complex of claim 30, wherein the body of heat transfers fluid comprises ethylene glycol.

32. The fluid complex of claim 31, wherein the body of heat transfers fluid also contains sodium do-decal sulfate.

33. The fluid complex of claim 1, wherein nanoparticles have a length to diameter (l/d) of greater than one (1).

34. The fluid complex of claim 33, wherein the l/d ratio is at least two (2).

35. The fluid complex of claim 1, wherein the nanoparticles have a cross sectional size of less than 100 nanometers.

36. The fluid complex of claim 35, wherein the nanoparticles have a cross sectional size of less than 25 nanometers.

37. The complex of claim 1, wherein the thermal conductivity of said heat transfer fluid is further enhanced by the presence of a coupling agent in said complex.

38. The complex of claim 37, wherein the coupling agent consists essentially of an organic radical bonded to said nanoparticles.

39. The complex of claim 37, wherein the coupling agent comprises a metallic element.

40. The complex of claim 39, wherein the metallic element is present as a constituent of a metallic alloy.

41. The complex of claim 39, wherein the metallic element is encapsulated within the carbon nanoparticles.

42. The complex of claim 37, wherein the carbon nanoparticle is a fullerene or nanotube, wherein the coupling agent is attached thereto and is a functionalized derivative represented by the formula F(—

X —

R —

Z)n, wherein F is the fullerene or nanotube, wherein each X is independently —

CH₂—

, —

CHY—

(where Y=alkyl, aryl or alkylryl), —

O—

, —

S—

, —

N—

, —

C (O)—

, CO₂—

, —

CONH—

, —

CONY—

(where Y=alkyl, or aryl), —

OP (O)—

O₂, wherein each R is independently an alkyl, aryl, alkyl aryl, alkyl ether, aryl ether, alkylaryl ether, or —

C(O)— and

wherein, each Z is independently —

H, OH, SH, —

NH₂, NHY (where Y=alkyl, aryl or akylaryl), —

NC, CO₂Y (where Y═

H, alkyl, aryl,) arylalkyl, or a metal cation), alkyl, aryl, alkylaryl, alkyl ether, aryl ether, alkylaryl ether.

43. The complex of claim 12, wherein the single-wall nanotubes contain a covalently bonded functional group that has an interaction with the heat transfer fluid comprising the body of heat transfer fluid, whereby the suspension retention of the suspended nanoparticles are enhanced.

44. The complex of claim 43, wherein the functional group consists essentially of polyether chains bonded to the single-wall nanotubes.

45. The complex of claim 44, wherein the polyether includes a terminal alcohol group that enhances the suspension of the nanotubes in water.

46. The complex of claim 44, wherein the body of heat transfer fluid is comprised essentially use this of water.

47. The complex of claim 45, wherein the body of heat transfer fluid is comprised essentially use this of water.

48. The complex of claim 4, wherein the diamond nanoparticles are suspended in a body of heat transfer fluid comprising of ethylene glycol.

49. The complex of claim 4, wherein the diamond nanoparticles are suspended in a body of heat transfer fluid comprising of water.

50. The complex of claim 4, wherein the body of heat transfer fluid is comprised of a mixture of ethylene glycol and water.

51. The complex of claim 48, wherein the diamond nanoparticles are encapsulated in polycyclic ether to enhance the suspension in the heat transfer fluid.

52. The complex of claim 48, wherein the diamond nanoparticles are encapsulated in cyclo dextrin to enhance their suspension in the heat transfer fluid.

53. The complex of claim 51, wherein the polycyclic ether is present in equimolar amount of the diamond nanoparticles.

54. The complex of claim 52, wherein the cyclo dextrin is present in equimolar amount of diamond nanoparticle.

55. The complex of claim 42, wherein the carbon nanoparticle is a fullerene or nanotube, wherein the coupling agent is attached thereto and of polyalkyl substituted fullerene or adducts or polyalkyl substituted carbon nanotube adducts, wherein F is the fullerene or carbon nanotube core, respectively, wherein X is methylene (CH₂);

wherein, R is a hydrogen or (CH₂)n, with n being (1) or greater than one (1), and;

wherein, Z is a hydrogen (H).

56. The complex of claim 55, wherein X is CH₂ and R is H, whereby the fullerene and carbon nanotube adducts are polymethyl substituted fullerene and carbon nanotubes, respectively.

2. In a method of transferring heat energy between thermally separated first and second bodies comprising flowing a fluid heat transfer agent in a closed path between said first and second bodies wherein successive portions of the heat transfer agent pass in heat exchange relationship with each of said first and second bodies whereby heat energy is transferred from the hotter of said bodies to the colder body when they are at different temperatures, the improvement wherein said heat transfer agent consists essentially of a fluid complex comprising a body of heat transfer fluid having suspended therein carbon nanoparticles comprised of carbon selected from carbon in the forms of sp² bonding and sp³ type bonding in a quantity sufficient to enhance thermal conductivity of said fluid as compared to the thermal conductivity of said heat transfer fluid per se.