PREPARATION OF NANOPARTICLE MATERIAL

• US 20090139574A1
• Filed: 11/26/2008
• Published: 06/04/2009
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: Nanoco Technologies Limited (Nanoco Group Plc)
• Original Assignee: Nanoco Technologies Limited (Nanoco Group Plc)
• Inventors: Pickett, Nigel, Harris, James
• Granted Patent: US 8,784,701 B2
• Time in Patent Office: Days
• US Class Current: 136/265
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C09D 11/037 characterised by the pigment
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: H01B 1/02 mainly consisting of metals or alloys
• CPC Class Codes: H01L 31/0322 comprising only AIBIIICVI chalcopyrite compounds, e.g. Cu In Se2, Cu Ga Se2, Cu In Ga Se2
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
• CPC Class Codes: H01L 31/072 the potential barriers being only of the PN heterojunction type
• CPC Class Codes: H01L 31/18 Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A process for producing nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, and materials produced by the process. In an embodiment, the process includes effecting conversion of a nanoparticle precursor composition comprising group 13, 16, and 11 or 12 ions to the material of the nanoparticles in the presence of a selenol compound. Other embodiments include a process for fabricating a thin film including nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table as well as a process for producing a printable ink formulation including the nanoparticles.

Claims

1. A process for producing nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, the process comprising:

effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to a material of the nanoparticles in the presence of a selenol compound.

2. A process according to claim 1, wherein the selenol compound comprises or consists essentially of an organoselenol compound.

3. A process according to claim 1, wherein the selenol compound comprises or consists essentially of at least one of 1-octane selenol or 1-dodecane selenol.

4. A process according to claim 1, wherein said organoselenol compound comprises or consists essentially of a volatile organoselenol compound.

5. A process according to claim 1, wherein the process further comprises dispersing at least a first portion of the nanoparticle precursor composition in a solvent.

10. A process according to claim 1, wherein the group 16 ions comprise or consist essentially of selenium ions.

13. A process according to claim 1, wherein the nanoparticles are represented by the formula

AB_1-xB′

_xSe_2-yC_y

where

A is selected from the group consisting of Cu, Zn, Ag and Cd;

B and B′

are each independently selected from the group consisting of Al, In and Ga;

C is selected from the group consisting of S and Te;

0≦

x≦

1;

0≦

y≦

2;

subject to the proviso that where x>

0, B′

≠

B.

17. A process according to claim 1, wherein the nanoparticles are selected from the group consisting of CuInSe₂;

CuIn_xGa_1-xSe₂;

CuGa₂Se₂;

ZnInSe₂;

ZnIn_xGa_1-xSe₂;

ZnGa₂Se₂;

AgInSe₂;

AgIn_xGa_1-xSe₂;

AgGa₂Se₂;

CuInSe_2-yS_y;

CuIn_xGa_1-xSe_2-yS_y;

CuGa₂Se_2-yS_y;

ZnInSe_2-yS_y;

ZnIn_xGa_1-xSe_2-yS_y;

ZnGa₂Se_2-yS_y;

AgInSe_2-yS_y;

AgIn_xGa_1-xSe_2-yS_y; and

AgGa₂Se_2-yS_y, where 0≦

x≦

1 and 0≦

y<

2.

6. (canceled)

7. (canceled)

8. (canceled)

9. (canceled)

11. (canceled)

12. (canceled)

14. (canceled)

15. (canceled)

16. (canceled)

18. A process for producing nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table and a volatile capping agent, the process comprising:

effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to a material of the nanoparticles in the presence of a volatile selenol compound that acts as said capping agent in the produced nanoparticles.

19. (canceled)

20. A process for producing a printable ink formulation comprising nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, the process comprising:

producing said nanoparticles by effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to a material of the nanoparticles in the presence of a selenol compound; and

combining said nanoparticles with a suitable ink base.

21. A process according to claim 20, wherein said ink base comprises one or more organic compounds.

22. A process according to claim 20, wherein a sufficient quantity of said nanoparticles are combined with said ink base such that the resulting ink formulation comprises up to 50% w/v of said nanoparticles.

23. A printable ink formulation comprising:

nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table; and

a suitable ink base.

24. A printable ink formulation according to claim 23, wherein the formulation comprises up to 50% w/v of said nanoparticles.

53. The printable ink formulation of claim 23, wherein said nanoparticles are produced by effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to a material of the nanoparticles in the presence of a selenol compound.

25. (canceled)

26. (canceled)

27. (canceled)

28. A process for fabricating a thin film comprising nanoparticles incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, the process comprising:

producing the nanoparticles by effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to a material of the nanoparticles in the presence of a selenol compound; and

forming said thin film.

29. A process according to claim 28, wherein the formation of said film comprises depositing a formulation containing said nanoparticles onto a supporting layer under conditions permitting formation of said thin film on said supporting layer.

30. A process according to claim 29, wherein formation of said film comprises at least one annealing cycle, the annealing cycle comprising a series of steps in which the temperature of the nanoparticle formulation deposited on the supporting layer is repeatedly increased and subsequently maintained at said increased temperature for a predetermined period of time, following which the nanoparticle formulation is cooled to form the film.

31. A process according to claim 30, wherein the highest temperature to which the nanoparticle formulation is heated during said at least one annealing process is below the vaporization temperature of selenium at the pressure at which heating is being effected.

36. A process according to claim 30, wherein the at least one of the annealing cycles is effected under a static atmosphere.

39. A process according to claim 29, wherein formation of said film comprises first and second annealing cycles, the first annealing cycle increasing the temperature of the nanoparticle formulation to a first maximum temperature and the second annealing cycle increasing the temperature of the nanoparticle formulation to a second maximum temperature, said second maximum temperature being higher than said first maximum temperature.

32. (canceled)

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37. (canceled)

38. (canceled)

40. (canceled)

41. (canceled)

42. (canceled)

43. (canceled)

44. A process for fabricating a thin film comprising semiconductor nanoparticles incorporating first and second ions, the process comprising:

depositing a layer of a formulation containing said nanoparticles on to a supporting layer; and

subsequently annealing said deposited nanoparticle-containing layer under a static atmosphere.

45. (canceled)

46. (canceled)

47. A photovoltaic device layer comprising:

a nanoparticle material incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, said nanoparticle material produced by effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to the nanoparticle material in the presence of a selenol compound.

48. (canceled)

49. A method of fabricating a photovoltaic device, the method comprising:

providing a first layer of material; and

providing a layer on said first layer, the layer comprising a nanoparticle material incorporating ions selected from groups 13, 16, and 11 or 12 of the periodic table, said nanoparticle material produced by effecting conversion of a nanoparticle precursor composition comprising said group 13, 16, and 11 or 12 ions to the nanoparticle material in the presence of a selenol compound.

50. A method according to claim 49, wherein said first layer comprises molybdenum.

51. (canceled)

52. (canceled)