Studying charge transport properties of organic photovoltaics at metal surfaces using two photon photoemission

James E. Johns, Eric Muller, C. B. Harris

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The efficiency of organic photovoltaics is often limited by the poor charge and exciton transport properties of the light harvesting components. Time and angle resolved two photon photoemission is used to directly study the ultrafast properties of the optically excited states in these materials which determine its photoconductivity. Time resolved band structures for both unsubstituted sexithiophene (6T) and (a, ?)-dihexyl-sexithiophene (DH6T) have been obtained on Ag(111). Following the initial excitation, both 6T and DH6T have nearly free electron like dispersions in the LUMO and LUMO+1; however, they have very different temporal evolution. Excitations in 6T decay in 30 fs. In DH6T, many of the electrons interact strongly with the hexane chains to form a bound small polaron which lives for more than 150 fs. The effects on charge transport of adding large, insulating side chains to organic semiconductors will be discussed based on these results.

Original languageEnglish (US)
Title of host publicationAmerican Chemical Society - 237th National Meeting and Exposition, ACS 2009, Abstracts of Scientific Papers
StatePublished - Dec 1 2009
Event237th National Meeting and Exposition of the American Chemical Society, ACS 2009 - Salt Lake City, UT, United States
Duration: Mar 22 2009Mar 26 2009

Publication series

NameACS National Meeting Book of Abstracts
ISSN (Print)0065-7727

Other

Other237th National Meeting and Exposition of the American Chemical Society, ACS 2009
CountryUnited States
CitySalt Lake City, UT
Period3/22/093/26/09

Fingerprint Dive into the research topics of 'Studying charge transport properties of organic photovoltaics at metal surfaces using two photon photoemission'. Together they form a unique fingerprint.

Cite this