Semiconductor nanocrystals and compositions and devices including same
View Patent ↗A semiconductor nanocrystal capable of emitting light with an improved photoluminescence quantum efficiency. The present invention further relates to compositions and devices including semiconductor nanocrystals capable of emitting light with an improved photoluminescence quantum efficiency. A semiconductor nanocrystal wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 50% upon excitation and including a maximum peak emission with a FWHM less than 20 nm is disclosed. Also disclosed are a device, a population of semiconductor nanocrystals, and a composition including a semiconductor nanocrystal wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 50% upon excitation and including a maximum peak emission with a FWHM less than 20 nm. A semiconductor nanocrystal that is capable of emitting light upon excitation with a photoluminescence quantum efficiency greater than about 90%. Also disclosed are a device, a population, and a composition including a semiconductor nanocrystal.
1. A semiconductor nanocrystal comprising a core comprising a first semiconductor material, the first semiconductor material comprising an alloy, and a shell disposed over at least a portion of a surface of the core, the shell comprising a second semiconductor material, wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 85% upon excitation and including a maximum peak emission with a FWHM less than 20 nm.
2. A semiconductor nanocrystal in accordance with claim 1 wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 90% upon excitation.
3. A semiconductor nanocrystal in accordance with claim 1 wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 95% upon excitation.
4. A semiconductor nanocrystal in accordance with claim 1 wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency of about 100% upon excitation.
5. A semiconductor nanocrystal in accordance with claim 1 wherein the second semiconductor material comprises one or more chemical elements.
6. A semiconductor nanocrystal in accordance with claim 1 wherein one or more ligands are attached thereto.
7. A semiconductor nanocrystal in accordance with claim 1 wherein the shell has a thickness in a range from greater than about 0 to about 20 monolayers.
8. A semiconductor nanocrystal in accordance with claim 1 wherein the first semiconductor material comprises three or more chemical elements.
9. A semiconductor nanocrystal in accordance with claim 1 wherein the second semiconductor material comprises two or more chemical elements.
10. A semiconductor nanocrystal in accordance with claim 1 wherein the first semiconductor material comprises zinc, cadmium, and sulfur.
11. A semiconductor nanocrystal in accordance with claim 1 wherein the second semiconductor material comprises zinc and sulfur.
12. A semiconductor nanocrystal in accordance with claim 1 wherein the first semiconductor material comprises Zn x Cd 1-x S, wherein 0<x<1.
13. A semiconductor nanocrystal in accordance with claim 12 wherein 0<x≦0.5.
14. A semiconductor nanocrystal in accordance with claim 12 wherein the second semiconductor material comprises ZnS.
15. A composition comprising a semiconductor nanocrystal comprising a core comprising a first semiconductor material, the first semiconductor material comprising an alloy, and a shell disposed over at least a portion of a surface of the core, the shell comprising a second semiconductor material, wherein the semiconductor nanocrystal is capable of emitting light with a photoluminescence quantum efficiency greater than about 85% upon excitation and including a maximum peak emission with a FWHM less than 20 nm.
16. A composition in accordance with claim 15 wherein the composition further includes a polymer.
17. A composition in accordance with claim 15 wherein the composition further includes a pre-polymer.
18. A composition in accordance with claim 15 wherein the composition further includes an oligomer.
19. A composition in accordance with claim 15 wherein the composition further includes a small molecule.
20. A composition in accordance with claim 15 wherein the composition further includes an inorganic material.
21. A composition in accordance with claim 15 wherein the composition comprises a matrix.
22. A composition in accordance with claim 21 wherein the composition comprises a matrix in which the semiconductor nanocrystals are dispersed.
23. A composition in accordance with claim 21 wherein the matrix comprises an organic material.
24. A composition in accordance with claim 21 wherein the matrix comprises an inorganic material.
25. A composition in accordance with claim 15 the composition further includes a non-polar liquid in which the semiconductor nanocrystal is dispersible.
26. A composition in accordance with claim 15 the composition further includes a polar liquid in which the semiconductor nanocrystal is dispersible.
27. A composition in accordance with claim 15 wherein the first semiconductor material comprises Zn x Cd 1-x S, wherein 0<x<1.
28. A composition in accordance with claim 27 wherein 0<x≦0.5.
29. A composition in accordance with claim 27 wherein the second semiconductor material comprises ZnS.
30. A semiconductor nanocrystal in accordance with claim 1 wherein the core emits light including a maximum peak emission with a FWHM less than 20 nm prior to disposition of the shell.
31. A population of semiconductor nanocrystals comprising a semiconductor nanocrystal in accordance with claim 1 , wherein the population is capable of emitting light with a photoluminescence quantum efficiency greater than about 85% upon excitation and includes a maximum peak emission with a FWHM less than 20 nm.