Particles with quantum dots and method of making the same

Patent metadata

Field	Value
Publication number	US-2017190965-A1
Application number	US-201515313671-A
Country	US
Kind code	A1
Filing date	May 29, 2015
Priority date	Jun 3, 2014
Publication date	Jul 6, 2017
Grant date	—

Abstract

Particles comprising a composite core and a continuous inorganic coating covering the composite core, wherein the composite core comprises a continuous non-metallic inorganic matrix, ligands, and quantum dots, wherein the matrix comprise up to 40 volume percent, and wherein the coating has an average thickness up to 5 micrometers; and method of making the particles. Particles described here are useful, for example, to make articles (e.g., film).

First claim

1 . A particle comprising a composite core and a continuous inorganic coating covering the composite core, wherein the composite core comprises a continuous non-metallic inorganic matrix, ligands, and quantum dots, wherein the matrix comprise up to 40 volume percent, and wherein the coating has an average thickness up to 5 micrometers.

2 . The particle of claim 1 , wherein the matrix comprises at least one of silica or metal oxide.

3 . The particle of claim 1 , wherein at least 60 volume percent of the particle is collectively the ligands and the quantum dots, based on the total volume of the composite core.

4 . The particle of claim 1 , wherein the matrix is aerogel.

5 . The particle of claim 1 , wherein the composite core further comprises a liquid.

6 . The particle of claim 5 , wherein greater than 60 volume percent of the particle is collectively the liquid, the ligands, and the quantum dots, based on the total volume of the composite core.

7 . The particle of claim 5 , wherein the liquid has vapor pressure at 25° C. of greater than 1 torr.

8 . The particle of claim 1 , wherein the composite core comprises a mesoporous structure.

9 . The particle of claim 1 , wherein the particle has air stable light emission properties.

10 . A film comprising a plurality of particles of claim 1 .

11 . The film of claim 8 further comprising polymer.

12 . The film comprising the particle of claim 10 , wherein the film exhibits external quantum efficiencies greater than 50.

13 . A method of making a particle of claim 1 , the method comprising:
providing a liquid having quantum dots dispersed therein; infiltrating the liquid having the quantum dots into a porous inorganic particle; and encapsulating the infiltrated particle with a continuous inorganic coating to provide the particle.

14 . The method of claim 13 , wherein encapsulating the infiltrated particle with a continuous inorganic coating is done via at least one of chemical vapor deposition, atomic layer deposition, sputtering, or evaporation.

15 . The method of claim 13 , wherein encapsulating the infiltrated particle with the inorganic high barrier coating is done at a pressure of at least 0.5 atmosphere.

16 . The method of claim 14 , wherein encapsulating the infiltrated particle with an inorganic high barrier material coating is done via chemical vapor deposition not exceeding a temperature of chemical vapor deposition of 220° C.

17 . The method of claim 16 , wherein the deposition includes reacting a metal oxide precursor comprising at least one metal cation and a co-reactant to the metal oxide precursor and wherein the ratio of metal oxide precursor to the co-reactant is changed at least once during the process.

Assignees

• 3M Innovative Properties Co

Inventors

• Budd Kenton D
• Sharma Neeraj
• Dodge Bill H
• Heller Daimon K
• Haase Michael A
• Aksit Mahmut

Classifications

• C09K11/025

  non-luminescent particle coatings or suspension media · CPC title

• C09K11/02 Primary

  Use of particular materials as binders, particle coatings or suspension media therefor · CPC title

• C09K11/883

  with zinc or cadmium · CPC title

• H01L33/502

  Electricity · mapped topic

• H10H20/8512

  Wavelength conversion materials · CPC title