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Synthesis and investigation of donor-porphyrin-acceptor triads with long-lived photo-induced charge-separate states.

ABSTRACT: Two donor-porphyrin-acceptor triads have been synthesized using a versatile Suzuki-coupling route. This synthetic strategy allows the powerful donor tetraalkylphenylenediamine (TAPD) to be introduced into tetraarylporphyrin-based triads without protection. The thermodynamics and kinetics of electron transfer in the new triads are compared with a previously reported octaalkyldiphenyl-porphyrin triad exhibiting a long-lived spin-polarized charge separate state (CSS), from theoretical and experimental perspectives, in both fluid solution and in a frozen solvent glass. We show that the less favorable oxidation potential of the tetraaryl-porphyrin core can be offset by using C60 , as a better electron-acceptor than triptycenenaphthoquinone (TNQ). The C60 -porphyrin-TAPD triad gives a spin-polarized charge-separated state that can be observed by EPR-spectroscopy, with a mean lifetime of 16 ms at 10 K, which is longer than in the previously reported TNQ-porphyrin-TAPD triad, following the predicted trend from calculated charge-recombination rates.

SUBMITTER: Kelber JB

PROVIDER: S-EPMC6054115 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Synthesis and investigation of donor-porphyrin-acceptor triads with long-lived photo-induced charge-separate states.

Kelber Julien B JB Panjwani Naitik A NA Wu Di D Gómez-Bombarelli Rafael R Lovett Brendon W BW Morton John J L JJL Anderson Harry L HL

Chemical science 20150731 11

Two donor-porphyrin-acceptor triads have been synthesized using a versatile Suzuki-coupling route. This synthetic strategy allows the powerful donor tetraalkylphenylenediamine (<b>TAPD</b>) to be introduced into tetraarylporphyrin-based triads without protection. The thermodynamics and kinetics of electron transfer in the new triads are compared with a previously reported octaalkyldiphenyl-porphyrin triad exhibiting a long-lived spin-polarized charge separate state (CSS), from theoretical and ex ...[more]

PMID: 30090266

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Dataset Information

Synthesis and investigation of donor-porphyrin-acceptor triads with long-lived photo-induced charge-separate states.

Publications

Synthesis and investigation of donor-porphyrin-acceptor triads with long-lived photo-induced charge-separate states.

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