Acceptor Energy Level Control of Charge Photogeneration in Organic Donor/Acceptor Blends
Shoaee, Safa; Clarke, Tracey M.; Huang, Chun; Barlow, Stephen; Marder, Seth R.; Heeney, Martin; McCulloch, Iain; Durrant, James R.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
2010
In this paper we focus upon the role of interfacial energetics in influencing the separation of charge transfer states into dissociated charge carriers in organic donor/acceptor blend films. In particular, we undertake transient optical studies of films comprising regioregular poly(3-hexylthiophene) (P3HT) blended with a series of perylene-3,4:9,10-tetracarboxydiimide (PDI) electron acceptors. For this film series, we observe a close correlation between the PDI electron affinity and the efficiency of charge separation. This correlation is discussed in the context of studies of charge photogeneration for other organic donor/acceptor blend films, including other polymers, blend compositions, and the widely used electron acceptor 3′-phenyl-3′H-cyclopropa[1,9](C60-Ih)[5,6]fullerene-3′-butanoic acid methyl ester (PCBM).