Graded core/shell semiconductor nanorods and nanorod barcodes
Graded core/shell semiconductor nanorods and shapped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.
1. A method of growing a CdS/ZnS graded shell, comprising:
providing a core that comprises a semiconductor material,
combining the core with at least one surfactant to form a mixture,
heating the mixture, and
combining the mixture with a CdS/ZnS stock solution to produce graded core/shell nanorods.
2. The method of claim 1 , wherein:
the core is rod shaped.
3. The method of claim 2 , wherein:
the core comprises CdSe.
4. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the mixture is heated to a temperature between 100-360° C.
5. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the mixture is heated to a temperature of 160° C.
6. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the core is combined with only one surfactant.
7. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the surfactant is chosen from the group consisting of TOPO, TBP, HDA, HPA and TDPA.
8. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the mixture is kept at a temperature of approximately 160° C. for between 5 minutes and 24 hours after combining the CdS/ZnS stock solution.
9. The method of growing a CdS/ZnS graded shell of claim 8 , wherein:
the mixture is kept at a temperature of 160° C. for 10 minutes after combining the CdS/ZnS stock solution.
10. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the core is a shaped nanorod.
11. The method of growing a CdS/ZnS graded shell of claim 10 , wherein:
the core has a tetrapod shape.
12. The method of growing a CdS/ZnS graded shell of claim 1 , wherein:
the graded core/shell nanorods are photochemically annealed.
13. The method of growing a CdS/ZnS graded shell of claim 12 , wherein:
the annealing is done using an Ar+ laser.
14. A method of growing a CdS/ZnS graded shell, comprising:
providing a mixture comprising a core and a sufactant,
heating the mixture, and
combining the mixture with a CdS/ZnS stock solution.
15. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the core is rod shaped.
16. The method of growing a CdS/ZnS graded shell of claim 15 , wherein:
the core comprises CdSe.
17. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the mixture is heated to a temperature between 100-360° C.
18. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the mixture is heated to a temperature of 160° C.
19. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the mixture contains only one surfactant.
20. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the surfactant is chosen from the group consisting of TOPO, TBP, HDA, HPA and TDPA.
21. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the mixture is kept at a temperature of approximately 160° C. for between 5 minutes and 24 hours after combining the CdS/ZnS stock solution.
22. The method of growing a CdS/ZnS graded shell of claim 21 , wherein:
the mixture is kept at a temperature of 160° C. for 10 minutes after combining the CdS/ZnS stock solution.
23. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
the core is a shaped nanorod.
24. The method of growing a CdS/ZnS graded shell of claim 23 , wherein:
the core has a tetrapod shape.
25. A method of growing a graded core/shell semiconductor nanorod, comprising:
providing a semiconductor nanorod core,
combining the core with at least one surfactant to form a surfactant/core mixture,
heating the surfactant/core mixture, and
combining the surfactant/core mixture with a solution, wherein said solution comprises semiconductor precursors in a molar ratio sufficient to cause the growth of a graded semiconductor shell on the core.
26. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the semiconductor nanorod core comprises a semiconductor material selected from the group consisting of Group II-VI, Group III-V and Group IV semiconductors.
27. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the core is rod shaped.
28. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the core comprises CdSe.
29. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the surfactant/core mixture is heated to a temperature between 100-360° C.
30. The method of growing a graded core/shell semiconductor nanorod of claim 29 , wherein:
the surfactant/core mixture is heated to a temperature of 160° C.
31. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
only one surfactant is combined with the core.
32. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the surfactant is chosen from the group consisting of TOPO, TBP, HDA, HPA and TDPA.
33. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the surfactant/core mixture is kept at a temperature of approximately 160° C. for between 5 minutes and 24 hours after combining the solution.
34. The method of growing a graded core/shell semiconductor nanorod of claim 33 , wherein:
the surfactant/core mixture is kept at a temperature of 160° C. for 10 minutes after combining the solution.
35. The method of growing a graded core/shell semiconductor nanorod 25, wherein:
the core is a shaped nanorod.
36. The method of growing a graded core/shell semiconductor nanorod of claim 35 , wherein:
the core has a tetrapod shape.
37. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the graded core/shell nanorod is photochemically annealed.
38. The method of growing a graded core/shell semiconductor nanorod of claim 37 , wherein:
the annealing is done using an Ar+ laser.
39. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
the core comprises CdSe and the graded shell comprises CdS/ZnS.
40. The method of claim 1 , wherein:
a first monolayer on the core comprises CdS/ZnS.
41. The method of growing a CdS/ZnS graded shell of claim 14 , wherein:
a first monolayer on the core comprises CdS/ZnS.
42. The method of growing a graded core/shell semiconductor nanorod of claim 25 , wherein:
a first monolayer on the core comprises CdS/ZnS.