Quantum dot phosphor for light emitting diode and method of preparing the same

Abstract

Disclosed herein is a quantum dot phosphor for light emitting diodes, which includes quantum dots and a solid substrate on which the quantum dots are supported. Also, a method of preparing the quantum dot phosphor is provided. Since the quantum dot phosphor of the current invention is composed of the quantum dots supported on the solid substrate, the quantum dots do not aggregate when dispensing a paste obtained by mixing the quantum dots with a paste resin for use in packaging of a light emitting diode. Thereby, a light emitting diode able to maintain excellent light emitting efficiency can be manufactured.

1 . A quantum dot phosphor, comprising quantum dots and a solid substrate on which the quantum dots are supported.  
     
     
         2 . The quantum dot phosphor as set forth in  claim 1 , wherein the quantum dot is selected from the group consisting of Group II-VI compound semiconductor nanocrystals including CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe or HgTe, Group III-V compound semiconductor nanocrystals including GaN, GaP, GaAs, AlN, AlP, AlAs, InN, InP or InAs, and mixtures thereof.  
     
     
         3 . The quantum dot phosphor as set forth in  claim 2 , wherein the mixture is selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HggZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, or is selected from the group consisting of GaNP, GaNAs, GaPAs, AlNP, AlNAs, AlPAs, InNP, InNAs, InPAs, GaAlNP, GaAlNAs, GaAlPAs, GaInNP, GaInNAs, GaInPAs, InAlNP, InAlNAs and InAlPAs.  
     
     
         4 . The quantum dot phosphor as set forth in  claim 3 , wherein the mixture is partially divided and present in the same particles, or is present in a form of alloys.  
     
     
         5 . The quantum dot phosphor as set forth in  claim 1 , wherein the quantum dots are prepared by solution synthesis.  
     
     
         6 . The quantum dot phosphor as set forth in  claim 1 , wherein the substrate is i) metal oxide, a polymer, or a metal salt, ii) an inorganic phosphor, or iii) mixtures thereof.  
     
     
         7 . The quantum dot phosphor as set forth in  claim 6 , wherein the i) metal oxide is selected from the group consisting of SiO 2 , TiO 2 , Al 2 O 3  and mixtures thereof, the polymer is selected from the group consisting of polystyrene, polyimide, polyacrylate, polycarbonate, polyimidazole and mixtures thereof, and the metal salt is selected from the group consisting of KBr, NaBr, KI, KCl and NaCl.  
     
     
         8 . The quantum dot phosphor as set forth in  claim 6 , wherein the ii) inorganic phosphor is selected from the group consisting of ZnS:Ag, ZnS:Cu, ZnS:Mn, ZnS:Cu,Al, (Zn,Cd)S:Cu, (Zn,Cd)S:Ag, (Zn,Cd)S:Cu,Al, ZnS:Cu,Au,Al, ZnS:Ag,Cu,Ga,C 1 , Y 2 O 2 S:Eu, ZnS:Ag,Al, ZnO:Zn, BaMgAl 10 O 17 :Eu2+, (Sr,Ca,Ba,Mg) 10 (PO 4 ) 6 Cl 2 : Eu, Sr 10  (PO 4 ) 6 C 12 : Eu, (Ba, Sr, Eu) (Mg,Mn)Al 10 O 17 , (Ba, Eu) MgAl 10 O 17 , YVO 4 :Eu, and mixtures thereof.  
     
     
         9 . A method of preparing a quantum dot phosphor, comprising: 
 dispersing quantum dots in a dispersion solvent;    mixing the dispersed quantum dots with a solid substrate, to prepare a mixture; and    drying the mixture to remove the dispersion solvent from the mixture.    
     
     
         10 . The method as set forth in  claim 9 , wherein the quantum dots are prepared through a reaction at 25 to 400° C. for a period from 1 sec to 4 hr.  
     
     
         11 . The method as set forth in  claim 9 , wherein the dispersion solvent is selected from the group consisting of chloroform, toluene, octane, heptane, hexane, pentane, dimethylchloride, tetrahydrofuran, methanol, ethanol, propanol, butanol, and mixtures thereof.  
     
     
         12 . The method as set forth in  claim 9 , wherein the drying is performed at 20 to 200° C. for 0.5 to 8 hr.  
     
     
         13 . A light emitting diode, comprising the quantum dot phosphor of  claim 1 , a paste resin to mix with the quantum dot phosphor, an epoxy resin for lamp molding to surround the mixture, and a light source.  
     
     
         14 . The diode as set forth in  claim 13 , wherein the paste resin is a material which does not absorb light of a wavelength emitted from the light source of the diode.  
     
     
         15 . The diode as set forth in  claim 14 , wherein the paste resin is selected from the group consisting of epoxys, silicones, acryl based polymers, glass, carbonate based polymers, and mixtures thereof.  
     
     
         16 . The diode as set forth in  claim 13 , wherein the light source emits light of a wavelength ranging from 300 to 470 nm.  
     
     
         17 . A method of manufacturing a light emitting diode, comprising: 
 mixing the quantum dot phosphor prepared according to  claim 8  with a paste resin, to prepare a mixture; and    dispensing the mixture on a light emitting diode, and curing the dispensed mixture.