All-Polymer Photonic Microcavities Doped with Perylene Bisimide J-Aggregates

Thanks to exciting chemical and optical features, perylene bisimide (PBI) J-aggregates are ideal candidates to be employed for high-performance plastic photonic devices. However, they generally tend to form - stacked H-aggregates that are unsuitable for implementation in polymer resonant cavities. In this work, we demonstrate the efficient compatibilization of a tailored perylene bisimide forming robust J-aggregated supramolecular polymers into amorphous polypropylene. The new nanocomposite was then implemented into an all-polymer planar microcavity which provides strong and directional spectral redistribution of the J-aggregate photoluminescence, owing to a strong modification of the photonic states. A systematic analysis of the photoemitting processes, including photoluminescence decay and quantum yields, shows that the optical confinement in the polymeric microcavity does not introduce any additional nonradiative de-excitation pathways to those already found in the J-aggregate nanocomposite film and pave the way to PBI-based high-performance plastic photonic devices

Ultrafast Photoinduced Symmetry-Breaking Charge Separation and Electron Sharing in Perylenediimide Molecular Triangles

We report on a visible-light-absorbing chiral molecular triangle composed of three covalently linked 1,6,7,12-tetra(phenoxy)perylene-3,4:9,10-bis- (dicarboximide) (EDT) units. The rigid triangular architecture reduces the electronic coupling between the PDIs, so ultrafast symmetry-breaking charge separation is kinetically favored over intramolecular excimer formation, as revealed by femtosecond transient absorption spectroscopy. Photoexcitation of the PDI triangle dissolved in CH2Cl2 gives PDI+center dot-PDI-center dot in tau(CS) = 12.0 +/- 0.2 ps. Fast subsequent intramolecular electron/hole hopping can equilibrate the six possible energetically degenerate ion-pair states, as suggested by electron paramagnetic resonance/electron nuclear double resonance spectroscopy, which shows that one-electron reduction of the EDT triangle results in complete electron sharing among the three PDIs. Charge recombination of PDI+center dot PDI-center dot to the ground state occurs in tau(CR) = 1.12 +/- 0.01 ns with no evidence of triplet excited state formation