Controlled fabrication of semiconductor-metal hybrid nano-heterostructures via site-selective metal photodeposition
View Patent ↗A method of synthesizing colloidal semiconductor-metal hybrid heterostructures is disclosed. The method includes dissolving semiconductor nanorods in a solvent to form a nanorod solution, and adding a precursor solution to the nanorod solution. The precursor solution contains a metal. The method further includes illuminating the combined precursor and nanorod solutions with light of a specific wavelength. The illumination causes the deposition of the metal in the precursor solution onto the surface of the semiconductor nanorods.
1. A method of synthesizing colloidal semiconductor-metal hybrid heterostructures, the method comprising:
dissolving semiconductor nanorods in a solvent to form a nanorod solution;
adding a precursor solution to the nanorod solution, the precursor solution containing a metal;
illuminating the combined precursor and nanorod solutions with non-laser light of a specific wavelength, the illumination causing deposition of the metal in the precursor solution onto a surface of the semiconductor nanorods.
2. The method of claim 1 , wherein each of the semiconductor nanorods has an axially anisotropic morphology.
3. The method of claim 2 , wherein each of the semiconductor nanorods is oblong having a relatively thick first end that tapers to a relatively thin second end.
4. The method of claim 3 , wherein the specific wavelength of the non-laser light determines on which end a majority of the metal is deposited.
5. The method of claim 4 , wherein the specific wavelength of the non-laser light ranges from 350 nanometers to 575 nanometers.
6. The method of claim 1 , wherein the metal comprises palladium.
7. The method of claim 6 wherein the precursor solution comprises cis-dimethyl (N,N,N′,N′-tetramethylenediamine) palladium(II).
8. The method of claim 1 , wherein the metal comprises platinum.
9. The method of claim 8 wherein the precursor solution comprises dimethyl (1,5-cyclooctadiene) platinum (II).
10. The method of claim 1 , wherein the semiconductor nanorods comprise cadmium sulfide nanorods.
11. The method of claim 10 , wherein the cadmium sulfide nanorods have a wurzite crystal structure.
12. The method of claim 1 , wherein the solvent is toluene.
13. The method of claim 1 , wherein the nanorod solution has an optical density of approximately 1.2 at 470 nm or approximately 1.3 at 630 nm.
14. The method of claim 1 , wherein illuminating the combined precursor and nanorod solutions with non-laser light of a specific wavelength comprises illuminating the combined precursor and nanorod solutions with non-laser light of a specific wavelength for one to three hours.
15. The method of claim 1 , wherein illuminating the combined precursor and nanorod solutions with non-laser light of a specific wavelength comprises illuminating the combined precursor and nanorod solutions with non-laser light of a specific wavelength using fluorescent lamps.
16. The method of claim 1 , further comprising synthesizing the semiconductor nanorods to be dissolved.
17. The method of claim 16 , wherein synthesizing the semiconductor nanorods comprises:
mixing cadmium oxide, trioctylphosphine oxide, and octadecylphosphonic acid to form a mixture;
heating the mixture;
adding trioctylphosphine to the mixture, and then adding trioctylphosphine sulfide and trioctylphosphine selenide to the mixture;
diluting the mixture in a solvent; and
isolating cadmium sulphoselenide nanorods from the mixture.