Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5375626 | Chemical Physics | 2008 | 9 Pages |
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 20Â wt%. The reported dependence of solar cell efficiency on fullerene concentration may thus arise from other factors. However, there exists an acceptor concentration threshold (5Â 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.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Swati De, Tero Kesti, Manisankar Maiti, Fengling Zhang, Olle Inganäs, Arkady Yartsev, Torbjörn Pascher, Villy Sundström,