Photoinitiated Charge Transport through π-Stacked Electron Conduits in Supramolecular Ordered Assemblies of Donor−Acceptor Triads

Autor:	Raanan Carmieli, Joseph E. Bullock, Sarah M. Mickley, Joshua Vura-Weis, Michael R. Wasielewski
Rok vydání:	2009
Předmět:	chemistry.chemical_classification Chemistry Radical Supramolecular chemistry General Chemistry Electron acceptor Photochemistry Biochemistry Catalysis Photoexcitation chemistry.chemical_compound Colloid and Surface Chemistry Monomer Radical ion Molecule Methylcyclohexane
Zdroj:	Journal of the American Chemical Society. 131:11919-11929
ISSN:	1520-5126 0002-7863
DOI:	10.1021/ja903903q
Popis:	Photochemical electron donor-acceptor triads having an aminopyrene primary donor (APy) and a p-diaminobenzene secondary donor (DAB) attached to either one or both imide nitrogen atoms of a perylene-3,4:9,10-bis(dicarboximide) (PDI) electron acceptor were prepared to give DAB-APy-PDI and DAB-APy-PDI-APy-DAB. In toluene, both triads are monomeric, but in methylcyclohexane, they self-assemble into ordered helical heptamers and hexamers, respectively, in which the PDI molecules are pi-stacked in a columnar fashion, as evidenced by small- and wide-angle X-ray scattering. Photoexcitation of these supramolecular assemblies results in rapid formation of DAB(+*)-PDI(-*) spin-polarized radical ion pairs having spin-spin dipolar interactions, which show that the average distance between the two radical ions is much larger in the assemblies (31 A) than it is in their monomeric building blocks (23 A). This work demonstrates that electron hopping through the pi-stacked PDI molecules is fast enough to compete effectively with charge recombination (40 ns) in these systems, making these materials of interest as photoactive assemblies for artificial photosynthesis and organic photovoltaics.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5139aaae43baba60100e7629a84e961b https://doi.org/10.1021/ja903903q Zobrazit plný text záznamu