Rapid Energy Transfer Enabling Control of Emission Polarization in Perylene Bisimide Donor-Acceptor Triads.

Christopher Menelaou,Michael G Debije,Jeroen Ter Schiphorst,Amol M Kendhale,Laura M Herz,Patrick Parkinson,Albertus P H J Schenning

doi:10.1021/acs.jpclett.5b00183

Abstract

Materials showing rapid intramolecular energy transfer and polarization switching are of interest for both their fundamental photophysics and potential for use in real-world applications. Here, we report two donor-acceptor-donor triad dyes based on perylene-bisimide subunits, with the long axis of the donors arranged either parallel or perpendicular to that of the central acceptor. We observe rapid energy transfer (<2 ps) and effective polarization control in both dye molecules in solution. A distributed-dipole Förster model predicts the excitation energy transfer rate for the linearly arranged triad but severely underestimates it for the orthogonal case. We show that the rapid energy transfer arises from a combination of through-bond coupling and through-space transfer between donor and acceptor units. As they allow energy cascading to an excited state with controllable polarization, these triad dyes show high potential for use in luminescent solar concentrator devices.

Highlights

Luminescent solar concentrators (LSC)[3−5] are a separate class of concentrator devices based on a luminescent material embedded in a transparent lightguide
We directly compare the photophysics of the D−A−D triad in which D/A dipole moments are orthogonal with a triad in which the dipole moments are collinear
The broad absorption across much of the visible spectrum of these two dyes, along with the efficient energy transfer and PL polarization switching makes these dyes ideally suited to use in LSC devices

Summary

Introduction

Luminescent solar concentrators (LSC)[3−5] are a separate class of concentrator devices based on a luminescent material embedded in a transparent lightguide. A strong degree of electronic coupling is evident in the steady-state photoluminescence spectra (see Supporting Information) as the emission peak of the acceptor incorporated into the triads TL (TH) is red-shifted by 31.2 (42.4) meV relative to the isolated acceptor.

Results

Conclusion