In-situ encapsulation of quantum dots into polymer microspheres.
We have incorporated fluorescent quantum dots (QDs) into polystyrene microspheres using functionalized oligomeric phosphine (OP) ligands. We find that a uniform distribution of quantum dots is loaded inside each polymer bead. Some local close-packing of quantum dots in the beads is attributed to the self-polymerization of the functionalized ligands. The presence of quantum dots disturbs the nucleation and growth processes during the formation of polymer microspheres and results in a wider size distribution of the quantum dot-embedded polystyrene beads than for the control without dots. The change in quantum efficiency of the quantum dots before (approximately 20%) and after (12%) loading into the beads substantiates the protection of oligomeric phosphine ligands yet indicates that the properties of these quantum dots are still affected during processing.
Sheng
Wenchao
W
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA.
Kim
Sungjee
S
Lee
Jinwook
J
Kim
Sang-Wook
SW
Jensen
Klavs
K
Bawendi
Moungi G
MG
D019187:Cadmium Compounds / Q000737:chemistry; D008024:Ligands; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D008863:Microspheres; D008956:Models, Chemical; D008968:Molecular Conformation; D010720:Phosphines / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry; D015032:Zinc / Q000737:chemistry; D017967:Zinc Compounds / Q000737:chemistry
D019187:Cadmium Compounds; D008024:Ligands; D010720:Phosphines; D011108:Polymers; D011137:Polystyrenes; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C034939:cadmium sulfide; C058667:cadmium selenide; D015032:Zinc; C031238:zinc sulfide