Synthesis, photophysical, and device properties of novel dendrimers based on a fluorene-hexabenzocoronene (FHBC) core.

The synthesis of easily functionalized and highly soluble fluorene-containing hexabenzocoronenes (FHBC) has been achieved in high yield at a gram scale. Conjugated triarylamine oligomers were coupled to the FHBC cores via Buchwald-Hartwig coupling, and the photophysical properties of resulting dendritic materials were examined by ultrafast laser spectroscopic techniques. Efficient quenching of the triarylamine oligomer fluorescence was observed paving the way for the inclusion of these materials in bulk heterojunction solar cells. In preliminary studies, solar cell devices with external quantum efficiencies above 5% have been fabricated.