Photoinduced Electron Transfer between C₆₀/C₇₀ and Zinc Tetraphenylporphyrin in Polar Solvents

Abstract

Photoinduced electron transfer between C60/C70 and zinc tetraphenylporphyrin (ZnTPP) in a polar solvent has been investigated with a nanosecond laser photolysis method by observing the transient absorption bands in the near-IR region. The transient absorption bands of the C60/C70 radical anion (C60 •-/C70 •-) in the near-IR region gave evidence of electron transfer for the system ZnTPP and C60/C70. In ZnTPP solution where C60 and C70 were photoexcited predominantly, electron transfer takes place from the ground state of ZnTPP to the triplet states of C60/C70 (3C60*/3C70*). In the concentrated ZnTPP solution where ZnTPP was predominantly photoexcited, the triplet state of ZnTPP donates the electron to the ground state of C60/C70, producing C60 •-/C70 •-. The efficiency of electron transfer via the 3C60*/3C70* route is higher than that via 3ZnTPP*.

Photoinduced electron transfer from triplet states of phthalocyanines to fullerenes studied by transient absorption spectroscopies in visible and near-IR regions

“…Summarizing the results of the present study and our previous related studies [17,45,46], we have drawn the following conclusions.…”

“…In addition, since the absorption bands of ZnTBPc are more wide and intense in the visible region than those of C 60 /C 70 , the utilization of solar energy for PET via 3 ZnTBPc* is more effective than PET via 3 C 60 */ 3 C 70 *. (3) 3 ZnTBPc as well as the triplet excited states of porphyrins [45] may be useful in various areas of PET, including modelling of photosynthetic solar energy conversion. Our final goal is to find an efficient light-energy conversion system.…”

A thermochemical study of 5,10,15,20-tetraphenylporphine zinc(II) by rotating bomb combustion calorimetry and by Knudsen effusion experiments

“…Zinc porphyrins combined with fullerenes have a promotion of photoinduced electron transference in electrochemical cells. (19,20) Dimers (21) and other polymer arrays (22,23) of these porphyrins are used as models of photosynthetic light harvesting and energy transference systems. Another multiporphyrin systems can be designed in order to reach specific necessities.…”

Surface transfer doping of diamond with a molecular heterojunction

“…Surface transfer doping of diamond using such a molecular heterojunction has not been reported in the literature, but this approach would be potentially valuable because a diverse range of interesting molecular systems exist with intermolecular interactions that may be functionalised via a response to electrical, magnetic or optical excitation. 7 This paper explores the effect of the introduction of an intralayer of zinc-tetraphenylporphyrin (ZnTPP) between an acceptor layer and the underlying H-terminated diamond surface. The addition of a ZnTPP layer is found to prevent the development of a surface conductivity upon the subsequent exposure to air but permit fluorofullerene-induced surface conductivity.…”