Catalytic Effects of Dioxygen on Intramolecular Electron Transfer in Radical Ion Pairs of Zinc Porphyrin-Linked Fullerenes

2001 ◽  
Vol 123 (11) ◽  
pp. 2571-2575 ◽  
Author(s):  
Shunichi Fukuzumi ◽  
Hiroshi Imahori ◽  
Hiroko Yamada ◽  
Mohamed E. El-Khouly ◽  
Mamoru Fujitsuka ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Ion Pairs ◽  
Intramolecular Electron Transfer ◽  
Zinc Porphyrin ◽  
Catalytic Effects

Ultrafast Photodriven Intramolecular Electron Transfer from a Zinc Porphyrin to a Readily Reduced Diiron Hydrogenase Model Complex

2010 ◽  
Vol 132 (26) ◽  
pp. 8813-8815 ◽  
Author(s):  
Amanda P. S. Samuel ◽  
Dick T. Co ◽  
Charlotte L. Stern ◽  
Michael R. Wasielewski
Keyword(s):  
Electron Transfer ◽  
Intramolecular Electron Transfer ◽  
Zinc Porphyrin ◽  
Model Complex

Formation and photoinduced properties of zinc porphyrin-SWCNT and zinc phthalocyanine-SWCNT nanohybrids using diameter sorted nanotubes assembled via metal-ligand coordination and π–π stacking

2011 ◽  
Vol 15 (09n10) ◽  
pp. 1033-1043 ◽  
Author(s):  
Sushanta K. Das ◽  
Navaneetha K. Subbaiyan ◽  
Francis D'Souza ◽  
Atula S. D. Sandanayaka ◽  
Takatsugu Wakahara ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Steady State ◽  
Rate Constants ◽  
Charge Separation ◽  
Ion Pairs ◽  
Free Energy Calculations ◽  
Zinc Phthalocyanine ◽  
Ir Absorption ◽  
Zinc Porphyrin ◽  
Π Stacking

Photoinduced electron transfer processes in self-assembled zinc porphyrin ( ZnP ) or zinc phthalocyanine ( ZnPc ) with semiconducting (7,6)- and (6,5)-enriched SWCNTs were investigated. To bind photosensitizers to SWCNTs, first, pyrene covalently functionalized with a phenylimidazole (Im-Pyr) entity was treated with SWCNTs. Exfoliation of SWCNTs occurred due to π–π stacking of pyrene with nanotubes walls leaving the imidazole entity that was subsequently used to coordinate ZnP or ZnPc in o-dichlorobenzene (DCB). The donor-acceptor nanohybrids thus formed were characterized by TEM imaging, steady-state UV-visible-near IR absorption and fluorescence spectra. Free-energy calculations suggested possibility of electron transfer from the photoexcited ZnP or ZnPc to Im-Pyr/SWCNT(n,m) in the nanohybrids. Consequently, steady-state and time-resolved fluorescence studies revealed efficient quenching of the singlet excited state of ZnP or ZnPc with the rate constants of charge separation (k CS ) in the range of (3–6) × 109 s-1. Nanosecond transient absorption technique confirmed the electron transfer products, ZnP·+←Im-Pyr/SWCNT·- and ZnPc·+←Im-Pyr/SWCNT·- (and opposite charged pairs) having characteristic absorptions with the decay rate constants due to charge recombination (k CR ) in the range of (1.4–2.4) × 107 s-1, corresponding to lifetimes of radical ion-pairs in the 70–100 ns range. The SWCNT·- was further utilized to mediate electrons to hexyl-viologen dication (HV2+) resulting in an electron-accumulation process in the presence of sacrificial electron donor, offering additional proof for the occurrence of photoinduced charge-separation and potential utilization of these materials in light energy harvesting applications. Further, photoelectrochemical cells have been constructed on FTO/ SnO2 electrodes to verify their ability to directly convert light into electricity. An IPCE efficiency of up to 7% has been achieved in case of ZnP←Im-Pyr/SWCNT modified electrode.

Intramolecular Electron Transfer Mediated by a Tetrathiafulvalene Bridge in a Purely Organic Mixed-Valence System

2003 ◽  
Vol 42 (24) ◽  
pp. 2765-2768 ◽  
Author(s):  
Nicolas Gautier ◽  
Frédéric Dumur ◽  
Vega Lloveras ◽  
José Vidal-Gancedo ◽  
Jaume Veciana ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Mixed Valence ◽  
Intramolecular Electron Transfer
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