Tellurium-containing nanocrystalline materials
Tellurium-containing nanocrystallites are produced by injection of a precursor into a hot coordinating solvent, followed by controlled growth and annealing. Nanocrystallites may include CdTe, ZnTe, MgTe, HgTe, or alloys thereof. The nanocrystallites can photoluminesce with quantum efficiencies as high as 70%.
1. A method of manufacturing nanocrystallites, comprising
injecting into a coordinating solvent an M-containing compound, M being selected from the group consisting of Cd, Zn, Mg, and Hg, and a Te-containing compound of the form
wherein one of Z, Z′, and Z″ comprises an amide, to form a mixture; and
heating the mixture to grow the nanocrystallites.
2. The method according to claim 1 , wherein the Te-containing compound has a boiling point of at least 200° C. at atmospheric pressure.
3. The method according to claim 1 , wherein each of Z, Z′, and Z″ is an amide.
4. The method according to claim 1 , wherein each of Z, Z′, and Z″, independently, is —N(A)(A′), wherein each of A and A′, independently, is alkyl, alkenyl, aryl, cycloalkyl, or cycloalkenyl.
5. The method according to claim 1 , wherein each amide, independently, is a dialkyl amide.
6. The method according to claim 1 , further comprising mixing the Te-containing compound and the M-containing compound prior to injecting.
7. The method according to claim 1 , further comprising adding additional M-containing compound, additional Te-containing compound, or a mixture thereof, during heating.
8. The method according to claim 1 , wherein the Te-containing compound and the M-containing compound are injected sequentially.
9. The method according to claim 1 , wherein the Te-containing compound and the M-containing compound are injected substantially simultaneously.
10. The method according to claim 1 , further comprising growing an overcoating of a semiconductor on a surface of the nanocrystallite.
11. The method according to claim 1 , further comprising separating a size of nanocrystallite by size selective precipitation.
12. The method according to claim 11 , wherein an amine is added to the nanocrystallites during size selective precipitation.
13. The method according to claim 1 , wherein the nanocrystallite photoluminesces with a full-width at half maximum (FWHM) of 70 nm or less.
14. The method according to claim 1 , wherein the FWHM is 45 nm or less.