Donor-Linked Di(perylene bisimide)s: Arrays Exhibiting Fast Electron Transfer for Photosynthesis Mimics

Abstract

The first example of donor-linked di(perylene bisimide)s is reported. UV-vis absorption spectra of these newly synthesized dyads showed intense absorption across the entire visible region, demonstrating their excellent light-harvesting activities. The severe fluorescence quenching event probed by steady-state fluorescence spectroscopy and the free-energy calculations suggested the possibility of electron transfer (ET) in these arrays upon photoexcitation. Further femtosecond transient absorption spectra clarified that the fluorescence quenching was due to fast intramolecular ET. The rate of the charge separation (CS) was found to be as high as 10(12) s(-1) in CH(2)Cl(2). It was suggested that the large ET driving forces, strong donor-acceptor electronic coupling, and relatively small reorganization energy of diPBI accounted for the rapid ET process in a synergic manner. The fate of the generated radical ion pair depended on the solvent used. Rapid charge recombination to ground state occurred for the dyads in polar CH(2)Cl(2) and for diPBI-TPA in nonpolar toluene. However, sufficient (3)diPBI* population was attained via efficient spin-orbit coupled intersystem crossing from the charge-separated state for diPBI-PdTPP in toluene. These photophysical properties are interpreted as the cooperation between thermodynamic feasibility and kinetic manipulation.

DiiodoBodipy-Perylenebisimide Dyad/Triad: Preparation and Study of the Intramolecular and Intermolecular Electron/Energy Transfer

“…63 Similar results were also observed with the Bodipy-C 60 dyad and Si-phthalocyanine complex. 64 Therefore, the PET of the dyad and triad was studied.…”

“…63 Similar formation of the triplet state of C 60 was observed with Bodipy-C 60 dyad and Si-phthalocyanine complex. 64 However, for B-1 and B-2, the triplet excited states of the PBI moiety were not populated via the CR process.…”

Distance‐Dependent Electron Transfer Kinetics in Axially Connected Silicon Phthalocyanine‐Fullerene Conjugates

“…[1][2][3] Multichromophoric systems consisting of donor-acceptor assemblies are of great significance in designing new molecular architectures for artificial photosynthesis. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] To investigate their potential use in artificial photosynthesis, these molecular building blocks should demonstrate novel photophysical characteristics including high tunability in the UV-Vis spectrum and the ability to harvest sunlight. Porphyrinoid electron-donor, usually porphyrins and phthalocyanines, are preferred for building artificial photosynthetic systems, due to their high molar extinction coefficients and photo-tunability.…”

Synthesis of Molecular Dyads and Triads Based Upon N‐Annulated Perylene Diimide Monomers and Dimers

“…In the majority of these systems, the donor unit is tethered to the PDI though the imide position via an alkyl,, , aryl,, , , , or no linker, owing to ease of installing amine functionalized compounds at the imide positions. There are only a few examples of PDI based dyads being tethered at bay positions, either via alkoxy, or N‐annulated linkers.…”

“…This molecular design was further extended to dyad and triad systems based on a dimeric N‐annulated perylene diimide ( NPDI hex2 ) acceptor. Dimeric PDI based materials have been frequently used in high performance non‐fullerene electron acceptors in organic solar cells,, , but have yet to be fully exploited in dyad/triad type systems with only one system reported to date . The dyad 9 ( NPDI hex2 PTZ ) and triad 10 ( NPDI hex2 PTZ 2 ) were targeted and contain a dimeric NPDI based acceptor with one and two PTZ units, respectively, extending out from the N‐annulated bay position.…”