Chemistry Faculty Publications

Document Type

Article

Abstract

Understanding the excited-state dynamics in conjugated systems can lead to their better utilization in optical sensors, organic photovoltaics (OPVs), and organic light-emitting diodes (OLEDs). We present the synthesis of self-assembled coordination polymers comprising two types of fluorescent moieties: discrete fluorene oligomers of a well-defined length (n = 1-9) connected via aluminum(III) bis(8-quinolinolate)acetylacetone joints. Due to their well-defined structure, these materials allowed for a detailed study of energy migration processes within the materials. Thus, femtosecond transient spectroscopy was used to study the ultrafast energy transfer from the oligofluorene to the quinolinolate moieties, which was found to proceed at a rate of 10(11) s(-1). The experimental results were found to be in agreement with the behavior predicted according to the Beljonne's improved Forster model of energy transfer. In addition, the solid-state and semiconductor properties of these coordination polymers allowed for the fabrication of OLEDs. Preliminary experiments with simple two- and three-layer devices fabricated by spin-coating yield bright yellow electroluminescence with maximum brightness of 6000 cd/m(2), with a turn-on voltage of similar to 6 V and a maximum external quantum efficiency of up to 1.2%, suggesting their potential for use in PLED applications.

Publication Date

2-2009

Publication Title

Journal Of The American Chemical Society

DOI

https://doi.org/10.1021/ja805175w

Start Page No.

1787

End Page No.

1795

Included in

Chemistry Commons

COinS