Abstract
Exciton dynamics in alternating copolymer/fullerene solar cell blends have been investigated using femtosecond transient absorption spectroscopy. The acceptor concentrations have been varied over a wide range. Experimental data, kinetic modeling and simulations, all indicate that the efficiency of exciton conversion to charges is 100% even at acceptor concentrations as low as 20 wt%. The reported dependence of solar cell efficiency on fullerene concentration may thus arise from other factors. However, there exists an acceptor concentration threshold (5 wt%) below which a substantial fraction of the excitations remain unquenched. The results, we believe are very relevant to optimization of performance efficiency by clever manipulation of morphology. We have also observed exciton-exciton energy transfer in these blends at low acceptor concentrations. (C) 2007 Elsevier B.V. All rights reserved.
| Original language | English |
|---|---|
| Pages (from-to) | 14-22 |
| Journal | Chemical Physics |
| Volume | 350 |
| Issue number | 1-3 |
| DOIs | |
| Publication status | Published - 2008 |
Bibliographical note
The information about affiliations in this record was updated in December 2015.The record was previously connected to the following departments: Chemical Physics (S) (011001060)
Subject classification (UKÄ)
- Atom and Molecular Physics and Optics
Free keywords
- exciton dynamics
- polyfluorene/fullerene blends