Accession Number:

ADA460173

Title:

Spatial Position Control of CdS Nanoclusters using a Self-Assembled Diblock Copolymer Template

Descriptive Note:

Final rept., 30 Jun 2003-21 Sep 2004

Corporate Author:

NATIONAL CHIAO TUNG UNIV HSINCHU (TAIWAN) DEPT OF MATERIALS SCIENCE

Report Date:

2004-09-21

Pagination or Media Count:

25.0

Abstract:

Core-shell structured quantum dots QDs such as CdSeZnS and AuCdSeZnS nanoparticles are synthesized, and enhanced photoluminescent properties are observed in these nanoparticles as compared to that of bare core nanoparticles. For controlling the spatial position of nanoparticles with block copolymers, it was found that the mercapto-ethanol modified CdS nanoparticles have a preferential binding to the polyethylene oxide block of polystyrene-b-polyethylene oxide diblock copolymer, with a saturated concentration of 7 in volume fraction, and the composites have a better thermal stability. When CdS clusters have been sequestered into the PEO domain, the morphology of CdSPS-b-PEO composite thin film was found to be transformed from cylinders to spheres by the presence of hydrogen bonds between surface-hydroxylated CdS and PEO. In another case Pyridine-modified CdSe nanoparticles were found to selectively disperse in the poly4-vinylpyridine block of polystyrene-b-poly4-vinylpyridine diblock copolymer, with their luminescence retaining as in the pure state. Moreover, the photoluminescence and electroluminescence of the dendritic copolyfluorene are dramatically enhanced when a few percentage of CdS nanoparticles was incorporated.

Subject Categories:

  • Polymer Chemistry
  • Quantum Theory and Relativity

Distribution Statement:

APPROVED FOR PUBLIC RELEASE