Influence of nanoscale phase separation on geminate versus bimolecular recombination in P3HT:fullerene blend films

In this paper, we compare the charge recombination dynamics observed in films comprising poly(3-hexylthiophene) blended with three fullerene derivatives: PCBM and two alternative pyrazolinofullerenes. Transient absorption data indicate that replacement of PCBM with either of the pyrazolinofullerene...

Full description

Saved in:
Bibliographic Details
Published in:Energy & environmental science 2010, Vol.3 (7), p.971-976
Main Authors: Shoaee, Safa, Eng, Mattias P., Espíldora, Eva, Delgado, Juan Luis, Campo, Bert, Martín, Nazario, Vanderzande, Dirk, Durrant, James R.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this paper, we compare the charge recombination dynamics observed in films comprising poly(3-hexylthiophene) blended with three fullerene derivatives: PCBM and two alternative pyrazolinofullerenes. Transient absorption data indicate that replacement of PCBM with either of the pyrazolinofullerene derivatives results in a transition from bimolecular to monomolecular (geminate) recombination dynamics. We show that this transition cannot be explained by a difference in interfacial energetics. However, this transition does correlate with nanomorphology data which indicate that both pyrazolinofullerenes yield a much finer phase segregation, with correspondingly smaller domain sizes, than observed with PCBM. Our results therefore provide clear evidence of the role of nanomorphology in determining the nature of recombination dynamics in such donor/acceptor blends.
ISSN:1754-5692
1754-5706
DOI:10.1039/c003394d