Stabilized quantum dot composite and method of making a stabilized quantum dot composite

Patent metadata

Field	Value
Publication number	US-10347799-B2
Application number	US-201715809241-A
Country	US
Kind code	B2
Filing date	Nov 10, 2017
Priority date	Nov 10, 2017
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

A stabilized quantum dot composite includes a plurality of luminescent semiconducting nanoparticles embedded in a matrix comprising an ionic metal oxide. A method of making a stabilized quantum dot composite includes forming a mixture comprising a plurality of luminescent semiconducting nanoparticles dispersed in an aqueous solution comprising an ionic metal oxide. The mixture is dried to form a stabilized quantum dot composite comprising the plurality of luminescent semiconducting nanoparticles embedded in a matrix comprising the ionic metal oxide.

First claim

The invention claimed is:

1. A stabilized quantum dot composite comprising:
a plurality of luminescent semiconducting nanoparticles embedded in a matrix comprising an ionic metal oxide having a chemical formula nA x O y .mB z O w , wherein A includes one or more elements selected from the group consisting of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, wherein B includes one or more elements selected from the group consisting of B, Al, Ga, In, Si, Ge, Sn, and Pb, wherein x, y, z, and w are positive integers, and wherein n and m are stoichiometry coefficients.

2. The stabilized quantum dot composite of claim 1 having a morphology selected from the group consisting of: a microparticle, a coating, and a macroscopic body.

3. The stabilized quantum dot composite of claim 1 , wherein x=2, y=1, z=1, and w=2, and the chemical formula is nA 2 O.mBO 2 .

4. The stabilized quantum dot composite of claim 1 , wherein A comprises K, wherein B comprises Si, and wherein the ionic metal oxide comprises potassium silicate.

5. The stabilized quantum dot composite of claim 4 , wherein the potassium silicate comprises nK 2 O.mSiO 2 in a molar ratio n:m from about 1:1.5 to about 1:4.5.

6. The stabilized quantum dot composite of claim 1 , wherein the luminescent semiconducting nanoparticles comprise a semiconductor selected from the group consisting of: group IV, group II-VI semiconductors, group III-V semiconductors, group I-III-VI 2 semiconductors, and perovskite semiconductors.

7. The stabilized quantum dot composite of claim 6 , wherein an interior of each of the luminescent semiconducting nanoparticles comprises the semiconductor, and further comprising a buffer layer surrounding the interior.

8. The stabilized quantum dot composite of claim 7 , wherein the buffer layer comprises an oxide coating.

9. The stabilized quantum dot composite of claim 1 being optically transparent.

10. A light emitting device comprising:
a blue light emitting diode (LED) chip having a dominant wavelength of 425 nm to 475 nm in optical communication with the stabilized quantum dot composite of claim 1 for down conversion of light emitted from the blue LED chip.

11. The light emitting device of claim 10 disposed in a lighting fixture selected from the group consisting of: omnidirectional light bulb, candelabra bulb, downlight, troffer, street light, outdoor light, canopy light, parking garage light, waveguide-based troffer, waveguide-based garage light, and lamp.

12. The light emitting device of claim 10 , wherein a coating on the LED chip comprises the stabilized quantum dot composite.

13. The light emitting device of claim 10 , wherein an optical lens overlying the LED chip comprises the stabilized quantum dot composite.

14. The light emitting device of claim 10 , wherein a polymeric encapsulant on the LED chip comprises the stabilized quantum dot composite.

15. The light emitting device of claim 10 , wherein a coated substrate positioned remote from the LED chip comprises the stabilized quantum dot composite.

Assignees

• Cree Inc

Inventors

• Lotito Kenneth
• Gresback Ryan
• Griffiths Ceri
• Fini Paul

Classifications

• B82Y20/00

  Nanooptics, e.g. quantum optics or photonic crystals · CPC title

• F21K9/64

  using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer · CPC title

• Y10S977/892

  Liquid phase deposition · CPC title

• Y10S977/90

  having step or means utilizing mechanical or thermal property, e.g. pressure, heat · CPC title

• C09K11/025

  non-luminescent particle coatings or suspension media · CPC title