| AVS 55th International Symposium & Exhibition | |
| Surface Science | Wednesday Sessions |
| Session SS2-WeA |
| Session: | Electrons and Electronic Spectra at Surfaces |
| Presenter: | G. Dutton, National Institute of Standards and Technology |
| Authors: | G. Dutton, National Institute of Standards and Technology D.B. Dougherty, National Institute of Standards and Technology S.W. Robey, National Institute of Standards and Technology W. Jin, University of Maryland, College Park W.G. Cullen, University of Maryland, College Park J.E. Reutt-Robey, University of Maryland, College Park |
| Correspondent: | Click to Email |
The molecular donor-acceptor interface performs a critical function in the operation of organic photovoltaics as the sole site of charge separation. Understanding the electronic structure and exciton/polaron dynamics at these interfaces is crucial for developing the understanding of the relevant diffusion, dissociation and recombination processes necessary for achieving enhanced efficiencies. We have employed photoemission techniques, primarily two-photon photoemission spectroscopy (2PPE) and time-resolved pump-probe measurements, to examine these issues for thin organic films and heterointerfaces of pentacene and copper phthalocyanine with C60 fullerene. This talk will concentrate on results for interfaces between copper phthalocyanine and C60 formed on Ag(111). Using a combination of visible 1.75eV pump, corresponding to the phthalocyanine Q-band absorption maximum, and 5.25eV UV probe, we observe the ultrafast population dynamics of the C60 LUMO electron-polaron at 0.3 eV above the Fermi level. Preliminary analogies of corresponding physical molecular structures at this interface will also be presented based on STM results for the similar zinc phthalocyanine:C60 interface.