CPC H01L 33/06 (2013.01) [C01B 19/04 (2013.01); C09K 11/88 (2013.01); H01L 33/20 (2013.01); H01L 33/26 (2013.01)] | 19 Claims |
1. A method for preparing a core-shell quantum dot, comprising providing a core comprising a first semiconductor nanocrystal comprising zinc and selenium, and optionally sulfur and/or tellurium,
providing (i) a first solution comprising zinc-carboxylate, a fluorine ion source, and a solvent, or (ii) a second solution comprising ZnF2 and a solvent,
adding the core to the first solution or the second solution to provide a first core solution or a second core solution, respectively, and
adding at least one of a sulfur-containing precursor or a selenium-containing precursor, to the first core solution or the second core solution, and allowing the core solutions to react,
wherein the core-shell quantum dot has an average particle diameter of greater than or equal to about 13 nanometers, an emission peak wavelength in a range of about 440 nanometers to about 470 nanometers, and a full width at half maximum (FWHM) of an emission wavelength of less than about 25 nanometers, and
the core-shell quantum dot exhibits a quantum efficiency of greater than or equal to about 70%, and the core-shell quantum dot is cadmium-free.
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