Semiconductor Nanoparticle-Based Materials For Use in Light Emitting Diodes, Optoelectronic Displays and the Like

Abstract

A formulation incorporates nanoparticles, particularly quantum dot (QD) nanoparticles, into an optically clear medium (resin) to be used as a phosphor material in lighting and display applications, and as a down converting phosphor material in LEDs (light emitting diodes). The resin is compatible with QDs to allow high performance and stability of QD-based LEDs, lighting and display applications.

What is claimed is: 
     
         1 . A method of preparing a formulation for use in the fabrication of a light emitting device, said method comprising or consisting essentially of:
 incorporating a population of semiconductor nanoparticles comprising or consisting essentially of ions from groups 13 and 15 of the Periodic Table into an optically transparent poly(meth)acrylate encapsulation medium.   
     
     
         2 . A method according to  claim 1 , wherein said poly(meth)acrylate encapsulation medium is derived from a (meth)acrylate monomer and a trivalent crosslinking compound. 
     
     
         3 . A method of preparing a formulation for use in the fabrication of a light emitting device, said method comprising or consisting essentially of:
 incorporating a population of semiconductor nanoparticles into an optically transparent poly(meth)acrylate encapsulation medium derived from a (meth)acrylate monomer and a trivalent crosslinking compound.   
     
     
         4 . A method according to  claim 2  or  3 , wherein said monomer and crosslinking compound are reacted in the presence of a photoinitiator. 
     
     
         5 . A method of preparing a formulation for use in the fabrication of a light emitting device, said method comprising or consisting essentially of:
 incorporating a population of semiconductor nanoparticles into an optically transparent polymeric encapsulation medium derived from a laurylmethacrylate monomer and a trivalent crosslinking compound reacted in the presence of a photoinitiator.   
     
     
         6 . A method according to  claim 5 , wherein said monomer, crosslinking compound and photoinitiator are combined to provide an encapsulant precursor mixture to which is then added the semiconductor nanoparticles prior to polymerisation of said monomer to provide said optically transparent polymeric encapsulation medium. 
     
     
         7 . A method according to  claim 5 , wherein said semiconductor nanoparticles are produced by converting a nanoparticle precursor composition to the material of the nanoparticles in the presence of a molecular cluster compound under conditions permitting seeding and growth of the nanoparticles on the cluster compound. 
     
     
         8 . A method according to  claim 7 , wherein the nanoparticles incorporate first and second ions and the nanoparticle precursor composition comprises or consists essentially of separate first and second nanoparticle precursor species containing said first and second ions respectively for incorporation into the growing nanoparticles. 
     
     
         9 . A method according to  claim 7 , wherein the nanoparticles incorporate first and second ions and the nanoparticle precursor composition comprises or consists essentially of a single molecular species containing said first and second ions for incorporation into the growing nanoparticles. 
     
     
         10 . A light emitting device including or consisting essentially of a primary light source in optical communication with a formulation comprising or consisting essentially of a population of semiconductor nanoparticles comprising or consisting essentially of ions from groups 13 and 15 of the Periodic Table, said nanoparticles being incorporated into an optically transparent (meth)acrylate encapsulation medium. 
     
     
         11 . A light emitting device including or consisting essentially of a primary light source in optical communication with a formulation comprising or consisting essentially of a population of semiconductor nanoparticles incorporated into an optically transparent poly(meth)acrylate encapsulation medium derived from a (meth)acrylate monomer and a trivalent crosslinking compound. 
     
     
         12 . A light emitting device including or consisting essentially of a primary light source in optical communication with a formulation comprising or consisting essentially of a population of semiconductor nanoparticles incorporated into an optically transparent polymeric encapsulation medium derived from a laurylmethacrylate monomer and a trivalent crosslinking compound reacted in the presence of a photoinitiator. 
     
     
         13 . A device according to  claim 10 , wherein said primary light source is selected from the group consisting of a light emitting diode, a laser, an arc lamp, and a black-body light source. 
     
     
         14 . A device according to  claim 10 , wherein said formulation is in accordance with  claim 1 . 
     
     
         15 . A method of fabricating a light emitting device comprising or consisting essentially of:
 providing a population of semiconductor nanoparticles comprising or consisting essentially of ions from groups 13 and 15 of the Periodic Table in an optically transparent poly(meth)acrylate encapsulation medium to produce a nanoparticle-containing formulation, and depositing said formulation onto a primary light source such that said primary light source is in optical communication with said population of semiconductor nanoparticles.   
     
     
         16 . A method of fabricating a light emitting device comprising or consisting essentially of:
 providing a population of semiconductor nanoparticles in an optically transparent (meth)acrylate encapsulation derived from a (meth)acrylate monomer and a trivalent crosslinking compound medium to produce a nanoparticle-containing formulation, and depositing said formulation onto a primary light source such that said primary light source is in optical communication with said population of semiconductor nanoparticles.   
     
     
         17 . A method of fabricating a light emitting device comprising or consisting essentially of:
 providing a population of semiconductor nanoparticles in an optically transparent polymeric encapsulation medium derived from a laurylmethacrylate monomer and a trivalent crosslinking compound reacted in the presence of a photoinitiator to produce a nanoparticle-containing formulation, and depositing said formulation onto a primary light source such that said primary light source is in optical communication with said population of semiconductor nanoparticles.