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.
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA.
Wenchao
W
Sheng
Sungjee
S
Kim
Jinwook
J
Lee
Sang-Wook
SW
Kim
Klavs
K
Jensen
Moungi G
MG
Bawendi
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