Quantum dots tailored with electronically-active polymers
Cadmium selenide, and other quantum dot materials, can be integrated into thin films of poly(para-phenylene vinylene) (PPV) or other polymer compounds without aggregation of the nanocrystals. Solid-state photoluminescence spectra of composite materials prepared by these novel techniques reveal the effect of this greatly enhanced quantum dot-polymer interface relative to cases where the nanoparticles are aggregated, such that electronic communication and energy transfer between the nanoparticle and polymer components is made more efficient.
1. A conjugated polymeric ligand compound of a formula
wherein R 1 -R 2 and R 4 -R 11 are independently selected from H, alkyl, substituted alkyl, alkoxy, and substituted alkoxy moieties; m is an integer ranging from 0 to about 14; n is an integer ranging from 1 to about 12; and X is selected from halogen and vinyl substituents on the terminal phenylene-vinylene unit of said compound.
2. The ligand compound of claim 1 wherein n ranges from about 3 to about 6; and at least one of R 4 and R 5 , at least one of R 6 and R 9 , and at least one of R 10 and R 11 is selected from alkyl, substituted alkyl, alkoxy and substituted alkoxy moieties ranging from about C 1 to about C 14 .
3. The ligand compound of claim 2 wherein R 1 and R 2 are independently selected from alkyl and alkoxy moieties ranging from about C 6 to about C 14 .
4. The ligand compound of claim 3 wherein R 1 and R 2 are independently selected from linear alkyl and alkoxy moieties ranging from about C 8 to about C 12 .
5. The ligand compound of claim 3 coordinated with an emissive semi-conductor particulate, to provide a ligand-particulate composite.
6. The ligand compound of claim 5 wherein said particulate is selected from CdSe, ZnSe, CdTe, ZnTe and sulfide compositions thereof.
7. The ligand compound of claim 5 , said composite in a composition comprising a polymeric matrix component.
8. The ligand compound of claim 7 wherein said polymeric matrix component comprises the phenylene-vinylene moiety of said ligand compound.