Premium
Photochemical Charge Separation in Closely Positioned Donor–Boron Dipyrrin–Fullerene Triads
Author(s) -
Wijesinghe Channa A.,
ElKhouly Mohamed E.,
Subbaiyan Navaneetha K.,
Supur Mustafa,
Zandler Melvin E.,
Ohkubo Kei,
Fukuzumi Shunichi,
D'Souza Francis
Publication year - 2011
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201002446
Subject(s) - chemistry , fullerene , photochemistry , excited state , acceptor , boron , electron donor , electron transfer , electron acceptor , bodipy , femtosecond , singlet state , fluorescence , atomic physics , laser , organic chemistry , physics , quantum mechanics , optics , condensed matter physics , catalysis
A series of molecular triads, composed of closely positioned boron dipyrrin–fullerene units, covalently linked to either an electron donor (donor 1 –acceptor 1 –acceptor 2 ‐type triads) or an energy donor (antenna–donor 1 –acceptor 1 ‐type triads) was synthesized and photoinduced energy/electron transfer leading to stabilization of the charge‐separated state was demonstrated by using femtosecond and nanosecond transient spectroscopic techniques. The structures of the newly synthesized triads were visualized by DFT calculations, whereas the energies of the excited states were determined from spectral and electrochemical studies. In the case of the antenna–donor 1 –acceptor 1 ‐type triads, excitation of the antenna moiety results in efficient energy transfer to the boron dipyrrin entity. The singlet‐excited boron dipyrrin thus generated, undergoes subsequent energy and electron transfer to fullerene to produce a boron dipyrrin radical cation and a fullerene radical anion as charge‐separated species. Stabilization of the charge‐separated state in these molecular triads was observed to some extent.