PROCESS FOR MANUFACTURING COLLOIDAL NANOSHEETS BY LATERAL GROWTH OF NANOCRYSTALS

• US 20130220405A1
• Filed: 10/24/2011
• Published: 08/29/2013
• Est. Priority Date: 10/25/2010
• Status: Active Grant

• Current Assignee: Nexdot
• Original Assignee: Solarwell Co.
• Inventors: Ithurria, Sandrine, Mahler, Benoit
• Granted Patent: US 10,490,624 B2
• Time in Patent Office: Days
• US Class Current: 136/252
• 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: C30B 29/16 Oxides
• CPC Class Codes: C30B 29/46 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C30B 29/48 AIIBVI compounds wherein A is Zn, Cd or Hg, and B is S, Se or Te
• CPC Class Codes: C30B 29/60 characterised by shape
• CPC Class Codes: C30B 7/08 by cooling of the solution
• CPC Class Codes: H01L 21/02601 Nanoparticles fullerenes H10K85/211
• CPC Class Codes: H01L 29/04 characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes characterised by physical imperfections H01L29/30
• CPC Class Codes: H01L 31/0296 including, apart from doping material or other impurities, only AIIBVI compounds, e.g. CdS, ZnS, HgCdTe
• CPC Class Codes: H01L 31/032 including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
• 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 31/035218 the quantum structure being quantum dots
• CPC Class Codes: H01L 31/0384 including other non-monocrystalline materials, e.g. semiconductor particles embedded in an insulating material H01L31/0392 takes precedence
• CPC Class Codes: H01L 33/18 within the light emitting region
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells
• CPC Class Codes: Y10S 977/755 Nanosheet or quantum barrier/well, i.e. layer structure having one dimension or thickness of 100 nm or less
• CPC Class Codes: Y10S 977/932 for electronic or optoelectronic application

Abstract

A process for manufacturing colloidal nanosheet, by lateral growth, on an initial colloidal nanocrystal, of a crystalline semiconductor material represented by the formula M_nX_y, where M is a transition metal and X a chalcogen. The process includes the following steps: The preparation of a first organic solution, non or barely coordinating used as a synthesis solvent and including at least one initial colloidal nanocrystal; The preparation of a second organic solution including precursors of M and X, and including an acetate salt. And the slow introduction over a predetermined time scale of a predetermined amount of the second solution in a predetermined amount of the first solution, at a predetermined temperature for the growth of nanosheets. The use of the obtained material is also presented.

Claims

1-29. -29. (canceled)

30. A colloidal nanosheet comprising one initial colloidal nanocrystal extended laterally, and not in the thickness, by a different crystalline semiconductor material represented by the formula M_nX_y, wherein M is a transition metal and X a chalcogen.

31. The colloidal nanosheet according to claim 30, wherein said initial colloidal nanocrystal is made of CdO, CdS, CdSe, CdTe, ZnO, ZnS, ZnSe, ZnTe, PbO, PbS, PbSe, PbTe, HgS, HgSe, HgTe, CuInS₂, CuInSe₂, AgInS₂, AgInSe₂, CuS, Cu₂S, Ag₂S, Ag₂Se, Ag₂Te, FeS, FeS₂, InP, Cd₃P₂, Zn₃P₂, FeO, Fe₂O₃, Fe₃O₄, Al₂O₃, TiO₂, and alloy thereof.

32. The colloidal nanosheet according to claim 30, wherein said crystalline semiconductor material M_nX_y is a compound chosen among CdO, CdS, CdSe, CdTe, ZnO, ZnS, ZnSe, ZnTe, PbO, PbS, PbSe, PbTe, HgS, HgSe, HgTe, CuInS₂, CuInSe₂, AgInS₂, AgInSe₂, CuS, Cu₂S, Ag₂S, Ag₂Se, Ag₂Te, FeS, FeS₂, InP, Cd₃P₂, Zn₃P₂, FeO, Fe₂O₃, Fe₃O₄, Al₂O₃, TiO₂ and alloy thereof.

33. The colloidal nanosheet according to claim 30, wherein said semiconductor crystalline M_nX_y material is doped by a transition metal.

34. The colloidal nanosheet according to claim 30, wherein said colloidal nanosheet has a lateral size larger than 10 nm.

35. The colloidal nanosheet according to claim 30, wherein said initial colloidal nanocrystal is a colloidal nanosheet.

42. A large specific area material for catalysis comprising the colloidal nanosheet according to claim 30.

43. A light emitting diode comprising the colloidal nanosheet according to claim 30 as an active element.

44. A solar cell comprising the colloidal nanosheet according to claim 30 as an active element in an absorber and or in a collector of photogenerated charges.

45. A method of preparing a semiconductor ultrathin film comprising building said semiconductor ultrathin film on a substrate at low temperature from the colloidal nanosheet according to claim 30.

36. A method for manufacturing colloidal nanosheets on one initial colloidal nanocrystal, by lateral growth of a crystalline semiconductor material represented by the formula M_nX_y, where M is a transition metal and X a chalcogen, said process comprising the following steps:

Preparation of a first non or barely coordinating organic solution as a synthesis solvent including one initial nanocrystal,

Preparation of a second organic solution including precursors of M and X, and further including an acetate salt,

The slow introduction over a predetermined time scale of a predetermined amount of the second solution in a predetermined amount of the first solution, at a predetermined temperature for the growth of nanosheet.

37. The method according to claim 36, wherein said M precursor is a M phosphonate, a M dithiocarbamate, a M xanthate or a M carboxylate, in particular a M acetate, a M stearate, a M myristate or a M benzoate.

38. The method according to claim 36, wherein a ligand is added to the second solution, said ligand being preferably a carboxylic acid, an amine, a thiol, a phosphine or a phosphine oxide.

39. An homogeneous colloidal nanosheet obtainable by the method according to claim 36.

40. A heterogeneous colloidal nanosheet obtainable by the method according to claim 36, the initial nanocrystal having a different composition compared to the deposited M_nX_y material.

41. A colloidal nanosheet obtainable by the method according to claim 36, wherein said colloidal nanosheet comprises CdSe and said acetate salt is cadmium acetate.