COG as photosensitizing electron-transfer mediator for ion-pair charge-transfer complexes between borate anions and methyl viologen dication

Toshifumi Konishi, Mamoru Fujitsuka, Osamu Ito, Yasumasa Toba, Yoshiharu Usui

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

Photochemical reactions between the excited triplet state of C60 and the ion-pair charge-transfer complex which consists of electron-acceptor cation (methyl viologen (MV2)) and electron-donor anion (organo borates (~BPh3R, where R = Ph or Bu)) have been investigated by both steady-state and laser-flash photolysis. By photoirradiation of CM in the presence of MV2(-BPh3R)2 in organic solvents, the amount of MV+ increases with irradiation time, and persists for a long time even in the dark. From the laser-flash photolysis, it is found that electron transfer proceeds via 3C60 from -BPh3R in the complex, yielding ·BPh3R and C60-. Although generated Cr does not decay in the absence of MV2+ because of the rapid dissociation of BPh3R, in the presence of MV2+, C60- decays quickly by transferring an electron to MV2+ yielding MV+. Thus, it is proved that Ceo acts as a photosensitizer for pumping up an electron from -BPh3R as well as an electron mediator to MV2+. In these systems, MV+ persists even in air-saturated solution for more than an hour, suggesting that the electron transfer from MV+ to O2 is retarded.

Original languageEnglish
Pages (from-to)9938-9942
Number of pages5
JournalJournal of Physical Chemistry A
Volume103
Issue number48
Publication statusPublished - 1999 Dec 2
Externally publishedYes

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Borates
Paraquat
borates
Anions
Charge transfer
electron transfer
charge transfer
Ions
anions
Electrons
ions
electrons
flash
photolysis
Photolysis
decay
photochemical reactions
atomic energy levels
lasers
Photosensitizing Agents

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

COG as photosensitizing electron-transfer mediator for ion-pair charge-transfer complexes between borate anions and methyl viologen dication. / Konishi, Toshifumi; Fujitsuka, Mamoru; Ito, Osamu; Toba, Yasumasa; Usui, Yoshiharu.

In: Journal of Physical Chemistry A, Vol. 103, No. 48, 02.12.1999, p. 9938-9942.

Research output: Contribution to journalArticle

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AU - Konishi, Toshifumi

AU - Fujitsuka, Mamoru

AU - Ito, Osamu

AU - Toba, Yasumasa

AU - Usui, Yoshiharu

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