Preparation of nanoparticle materials

• US 7,803,423 B2
• Filed: 04/27/2005
• Issued: 09/28/2010
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Nanoco Technologies Limited (Nanoco Group Plc)
• Original Assignee: Nanoco Technologies Limited (Nanoco Group Plc)
• Inventors: O'Brien, Paul, Pickett, Nigel
• Primary Examiner(s): Cleveland; Michael
• Assistant Examiner(s): Jiang; Lisha
• Application Number:
  US11/579,050
• Publication Number:
  US 20070202333A1
• Time in Patent Office: 1,980 Days
• Field of Search: 427/212
• US Class Current: 427/213.34
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• 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 19/007 Tellurides or selenides of metals C01B19/002 takes precedence
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2004/84 one phase coated with the other
• CPC Class Codes: C01P 2006/60 Optical properties, e.g. expressed in CIELAB-values
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/025 non-luminescent particle coatings or suspension media
• CPC Class Codes: C09K 11/565 with zinc cadmium
• CPC Class Codes: C09K 11/621 Chalcogenides
• CPC Class Codes: C09K 11/70 containing phosphorus
• CPC Class Codes: C09K 11/7492 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/881 Chalcogenides
• CPC Class Codes: C09K 11/883 with zinc or cadmium
• CPC Class Codes: C09K 11/892 Chalcogenides
• 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 29/605 Products containing multiple oriented crystallites, e.g. columnar crystallites
• CPC Class Codes: C30B 7/00 Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions from molten solvents C30B9/00; by normal or gradient freezing C30B11/00; under a protective fluid C30B27/00
• CPC Class Codes: C30B 7/005 Epitaxial layer growth
• CPC Class Codes: C30B 7/10 : by application of pressure, e.g. hydrothermal processes
• CPC Class Codes: Y10S 977/774 : Exhibiting three-dimensional carrier confinement, e.g. quantum dots
• CPC Class Codes: Y10S 977/892 : Liquid phase deposition
• CPC Class Codes: Y10S 977/896 : Chemical synthesis, e.g. chemical bonding or breaking
• CPC Class Codes: Y10S 977/95 : Electromagnetic energy
• CPC Class Codes: Y10T 428/12861 : Group VIII or IB metal-base component
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]
• CPC Class Codes: Y10T 428/2989 : Microcapsule with solid core [includes liposome]
• CPC Class Codes: Y10T 428/2991 : Coated
• CPC Class Codes: Y10T 428/32 : Composite [nonstructural laminate] of inorganic material having metal-compound-containing layer and having defined magnetic layer

Abstract

A method of producing nanoparticles comprises effecting conversion of a nanoparticle precursor composition to the material of the nanoparticles. The precursor composition comprises a first precursor species containing a first ion to be incorporated into the growing nanoparticles and a separate second precursor species containing a second ion to be incorporated into the growing nanoparticles. The conversion is effected in the presence of a molecular cluster compound under conditions permitting seeding and growth of the nanoparticles.

Claims

1. A method of producing nanoparticles comprising:

effecting conversion of a nanoparticle precursor composition to a material of the nanoparticles, said precursor composition comprising a first precursor species containing a first ion to be incorporated into the nanoparticles and a separate second precursor species containing a second ion to be incorporated into the nanoparticles,

wherein said conversion is effected in the presence of a molecular cluster compound different from the first precursor species and the second precursor species under conditions permitting seeding and growth of the nanoparticles.

2. A method in accordance with claim 1, wherein a ratio of a number of moles of the cluster compound to a total number of moles of the first and second precursor species is selected from a range of 0.0001-0.1:

1.

3. A method in accordance with claim 1, wherein a molar ratio of the first precursor species to the second precursor species is selected from a range of 100-1:

1.

4. A method in accordance with claim 1, wherein the molecular cluster compound and nanoparticle precursor composition are dissolved in a solvent at a first temperature to form a solution and a temperature of the solution is then increased to a second temperature sufficient to initiate seeding and growth of the nanoparticles on the molecular clusters of said compound.

5. A method in accordance with claim 4, wherein the first temperature is selected from a range of 50°

C. to 100°

C.

6. A method in accordance with claim 4, wherein the second temperature is selected from a range of 120°

C. to 280°

C.

7. A method in accordance with claim 1, wherein effecting conversion of the nanoparticle precursor composition comprises:

a) monitoring an average size of the nanoparticles being grown; and

b) terminating nanoparticle growth when the average nanoparticle size reaches a predetermined value.

8. A method in accordance with claim 7, wherein nanoparticle growth is terminated by reducing the temperature of the solution from the second temperature to a third temperature.

9. A method in accordance with claim 8, wherein the third temperature is selected from a range of 50°

C. to 70°

C.

10. A method in accordance with claim 1, wherein the method comprises forming a precipitate of the nanoparticle material by addition of a precipitating reagent.

11. A method in accordance with claim 1, wherein the first precursor species is selected from the group consisting of an organometallic compound, an inorganic salt, and a coordination compound.

12. A method in accordance with claim 1, wherein the first precursor species is obtained by dissolving in a suitable solvent an elemental source selected from the group consisting of Mg, Ca, Sr, Ba, Zn, Cd, Hg, B, Al, Ga, In, Sn, and Pb.

13. A method in accordance with claim 1, wherein the second precursor species is selected from the group consisting of an organometallic compound, an inorganic salt, and a coordination compound.

14. A method in accordance with claim 1, wherein the second precursor species is obtained by dissolving in a suitable solvent an elemental source selected from the group consisting of Sn, Ge, N, P, As, Sb, Bi, S, Se, Te, Sn and Pb.

15. A method in accordance with claim 1, wherein the molecular cluster compound comprises a third ion and a fourth ion to be incorporated into the nanoparticles.

16. A method in accordance with claim 15, wherein the third ion is selected from group 12, 13, 14, or 15 or from the transition metal group of the periodic table and further wherein:

(i) if the third ion is selected from group 12 or 13 of the periodic table, then the fourth ion is selected from group 15 or 16 of the periodic table; and

(ii) if the third ion is selected from group 14 of the periodic table, then the fourth ion is selected from group 16 of the periodic table; and

(iii) if the third ion is selected from the transition metal group of the periodic table, then the fourth ion is selected from the d-block of the periodic table.

17. A method in accordance with claim 1, wherein the nanoparticles have cores comprising a core compound comprising fifth and sixth ions.

18. A method in accordance with claim 17, wherein each nanoparticle comprises at least one shell grown onto the nanoparticle core.

19. A method in accordance with claim 18, wherein the at least one shell has a lattice type similar to a lattice type of the nanoparticle core.

20. A method in accordance with claim 18, wherein the at least one shell has a wider band-gap than a band-gap of the nanoparticle core.

21. A method in accordance with claim 1, wherein the nanoparticles are ternary phase nanoparticles or quaternary phase nanoparticles.

22. A method in accordance with claim 1, wherein the nanoparticles comprise outer most layers comprising a capping agent.

23. A method in accordance with claim 22, wherein the capping agent is a solvent in which the nanoparticles are grown.

24. A method in accordance with claim 22, wherein the capping agent is a Lewis base.

25. A method of producing nanoparticles comprising effecting conversion of a nanoparticle precursor composition to a material of the nanoparticles, said precursor composition comprising a first precursor species containing a first ion to be incorporated into the nanoparticles and a separate second precursor species containing a second ion to be incorporated into the nanoparticles, said conversion being effected in the presence of a molecular cluster compound different from the first precursor species and the second precursor species under conditions permitting seeding and growth of the nanoparticles, wherein the molecular cluster compound and nanoparticle precursor composition are dissolved in a solvent at a first temperature to form a solution and the temperature of the solution is then increased to a second temperature which is sufficient to initiate seeding and growth of the nanoparticles on the molecular clusters of said compound.