title: Immobilizing water-soluble dendritic electron donors and electron acceptors-phthalocyanines and perylenediimides-onto single wall carbon nanotubes.
abstract: The complementary use of spectroscopy and microscopy sheds light onto mutual interactions between semiconducting single wall carbon nanotubes (SWNT) and either a strong dendritic electron acceptor-perylenediimide-or a strong dendritic electron donor-phthalocyanine. Importantly, the stability of the perylenediimide/SWNT electron donor-acceptor hybrids decreases with increasing dendrimer generation. Two effects are thought to be responsible for this trend. With increasing dendrimer generation we enhance (i) the hydrophilicity and (ii) the bulkiness of the resulting perylenediimides. Both effects are synergetic and, in turn, lower the immobilization strength onto SWNT. Owing to the larger size of the phthalocyanines, phthalocyanine/SWNT electron donor-acceptor hybrids, on the other hand, did not reveal such a marked dependence on the dendrimer generation. Several spectroscopies confirmed that distinct ground- and excited-state interactions prevail and that kinetically and spectroscopically well-characterized radical ion pair states are formed within a few picoseconds.
authors.affiliation: Departamento de Química Orgánica, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Uwe
authors.initials: U
authors.lastname: Hahn
authors.forename: Sarah
authors.initials: S
authors.lastname: Engmann
authors.forename: Christian
authors.initials: C
authors.lastname: Oelsner
authors.forename: Christian
authors.initials: C
authors.lastname: Ehli
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Guldi
authors.forename: Tomas
authors.initials: T
authors.lastname: Torres
mesh_terms: D050091:Dendrimers / Q000737:chemistry*; D004579:Electron Transport; D057927:Hydrophobic and Hydrophilic Interactions; D007094:Imides / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013057:Spectrum Analysis; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D050091:Dendrimers; D007094:Imides; D007211:Indoles; D054833:Isoindoles; D037742:Nanotubes, Carbon; D012997:Solvents; C521332:perylenediimide; D014867:Water; D011092:Polyethylene Glycols; D010569:Perylene; C013647:phthalocyanine