The exciton-dissociation and charge-recombination processes in donor-acceptor complexes found in α-sexithienyl/C60 and α-sexithienyl/perylenetetracarboxydiimide (PDI) solar cells are investigated by means of quantum-chemical methods. The electronic couplings and exciton-dissociation and charge-recombination rates have been evaluated for various configurations of the complexes. The results suggest that the decay of the lowest charge-transfer state to the ground state in the PDI-based devices: (i) is faster than that in the fullerene-based devices and (ii) in most cases, can compete with the dissociation of the charge-transfer state into mobile charge carriers. This faster charge-recombination process is consistent with the lower performance observed experimentally for the devices using PDI derivatives as the acceptor. © 2011 The Royal Society of Chemistry.
|Original language||English (US)|
|Journal||Journal of Materials Chemistry|
|State||Published - 2011|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS-C1-015-21
Acknowledgements: This article is dedicated to Professor Fred Wudl on the occasion of his 70th birthday. For nearly five decades, Fred has been at the forefront of the field of conducting and semiconducting organic materials; his impact on our research has been invaluable. We are deeply grateful for all we have learned from him and for his friendship. This work has been partially supported by the Office of Naval Research and the Center for Advanced Molecular Photovoltaics (Award No. KUS-C1-015-21 given by King Abdullah University of Science and Technology, KAUST).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.