Quantum Dots Stabilized With A Metal Thiol Polymer

Abstract

A composition of matter comprises a plurality of quantum dots and a metal thiol polymer that acts to stabilize the quantum dots. In certain embodiments, the metal thiol polymer is a zinc thiol polymer. The zinc thiol polymer may be a zinc alkanethiolate. The zinc alkanethiolate may be zinc dodecanethiolate (Zn-DDT). A composition comprising a plurality of quantum dots and a metal thiol polymer may be formulated with one or more additional polymers as a quantum dot-containing bead or as a quantum dot-containing composite material—e.g., a multilayer film.

What is claimed is: 
     
         1 . A method for preparing quantum dot beads comprising:
 preparing a first solution comprising a monomer, a cross-linker, and a polymerization photoinitiator;   dispersing quantum dots in the first solution to produce a second solution;   mixing the second solution with zinc thiol polymer to produce a third solution;   adding the third solution to an aqueous solution of polyvinyl alcohol and a surfactant under continuous stirring to form a fourth solution; and   exposing the fourth solution to ultraviolet light to form quantum dot beads.   
     
     
         2 . The method of  claim 1 , wherein the zinc thiol polymer is a zinc alkanethiolate. 
     
     
         3 . The method of  claim 2 , wherein the zinc alkanethiolate is zinc dodecanethiolate (Zn-DDT). 
     
     
         4 . Quantum dot beads prepared according to the method of  claim 1 . 
     
     
         5 . A method for preparing zinc dodecanethiolate (Zn-DDT) polymer comprising:
 adding a zinc salt to a synthetic heat transfer fluid to form a first solution;   annealing the first solution under an inert atmosphere;   adding dodecanethiol to the first solution in an amount relative to the amount of the anhydrous zinc salt used to provide a second solution;   annealing the second solution;   cooling the second solution; and   adding a non-solvent to precipitate Zn-DDT polymer.   
     
     
         6 . The method of  claim 5 , further comprising:
 dissolving the precipitated Zn-DDT in a non-polar solvent to produce a third solution and insoluble material; and   drying the insoluble material.   
     
     
         7 . The method of  claim 5 , further comprising:
 drying the precipitated Zn-DDT polymer to produce a powder consisting essentially of Zn-DDT polymer.   
     
     
         8 . The method of  claim 5 , wherein adding dodecanethiol to the first solution in an amount relative to the amount of anhydrous zinc salt used to provide a second solution comprises adding dodecanethiol in an amount such that the second solution has a Zn-to-S ratio of about 1:0.9. 
     
     
         9 . The method of  claim 5 , wherein the zinc salt is zinc acetate. 
     
     
         10 . The method of  claim 5 , wherein the zinc salt is zinc dimethacrylate. 
     
     
         11 . A method for preparing quantum dot beads comprising:
 preparing a first solution comprising a monomer, a cross-linker, and a polymerization photoinitiator;   dispersing quantum dots in the first solution to produce a second solution;   mixing the second solution with a Zn-DDT polymer produced according to the method of  claim 5  to produce a third solution;   adding the third solution to an aqueous solution of polyvinyl alcohol and a surfactant under continuous stirring to form a fourth solution; and   exposing the fourth solution to ultraviolet light to form quantum dot beads.   
     
     
         12 . A composite material comprising:
 quantum dots embedded in a resin comprising a Zn-DDT polymer produced according to the method of  claim 5 ,   wherein the quantum dots embedded in the resin comprising the Zn-DDT polymer are in the form of a ground composite powder.   
     
     
         13 . A composition of matter comprising:
 a plurality of quantum dots; and   a Zn-DDT polymer produced according to the method of  claim 5 .   
     
     
         14 . The composition recited in  claim 13 , further comprising a resin material different from the Zn-DDT polymer. 
     
     
         15 . The composition recited in  claim 13  formulated as a dry powder. 
     
     
         16 . The composition recited in  claim 13  formulated as a solution.