Abstract
Energy migration in self-assembled, water soluble, quantum dot (QD) nanoclusters is reported. These spherical nanoclusters are composed of CdSe QDs bound together by pepsin, a digestive enzyme found in mammals. A structural model for the clusters is suggested, based on scanning transmission electron microscopy, as well as dynamic light scattering and small angle X-ray scattering. Cluster sizes range from 100 to 400 nm in diameter and show a close-packed interior structure. Optical characterization of the absorption and emission spectra of the clusters is reported, finding photoluminescence quantum yields of up to approximately 60% in water for clusters made from core-shell CdSe-ZnS QDs. Clusters prepared from two different size populations of CdSe QD samples (3 and 4 nm in diameter) demonstrate energy migration and trapping. Resonance energy transfer (RET), from small to large dots within the QD-pepsin cluster, is observed by monitoring the quenching of the small donor dot fluorescence along with enhancement of the large acceptor dot fluorescence.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5079-5085 |
| Number of pages | 7 |
| Journal | Physical Chemistry Chemical Physics |
| Volume | 8 |
| Issue number | 43 |
| DOIs | |
| State | Published - 2006 |
| Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy
- Physical and Theoretical Chemistry