title: Tetrathiafulvalene-based nanotweezers-noncovalent binding of carbon nanotubes in aqueous media with charge transfer implications.
abstract: Electron donor-acceptor hybrids based on single wall carbon nanotubes (SWCNT) are one of the most promising functional structures that are currently developed in the emerging areas of energy conversion schemes and molecular electronics. As a suitable electron donor, π-extended tetrathiafulvalene (exTTF) stands out owing to its recognition of SWCNT through π-π stacking and electron donor-acceptor interactions. Herein, we explore the shape and electronic complementarity between different types of carbon nanotubes (CNT) and a tweezers-shaped molecule endowed with two exTTFs in water. The efficient electronic communication between semiconducting SWCNT/multiwall carbon nanotubes (MWCNT), on one hand, and the water-soluble exTTF nanotweezers 8, on the other hand, has been demonstrated in the ground and excited state by using steady-state as well as time-resolved spectroscopies, which were further complemented by microscopy. Importantly, appreciable electronic communication results in the electronic ground state having a shift of electron density, that is, from exTTFs to CNT, and in the electronic excited state having a full separation of electron density, that is oxidized exTTF and reduced CNT. Lifetimes in the range of several hundred picoseconds, which were observed for the corresponding electron transfer products upon light irradiation, tend to be appreciably longer in MWCNT/8 than in SWCNT/8.
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany.
authors.forename: Carlos
authors.initials: C
authors.lastname: Romero-Nieto
authors.forename: Raúl
authors.initials: R
authors.lastname: García
authors.forename: M Ángeles
authors.initials: MÁ
authors.lastname: Herranz
authors.forename: Christian
authors.initials: C
authors.lastname: Ehli
authors.forename: Michaela
authors.initials: M
authors.lastname: Ruppert
authors.forename: Andreas
authors.initials: A
authors.lastname: Hirsch
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Guldi
authors.forename: Nazario
authors.initials: N
authors.lastname: Martín
mesh_terms: D001665:Binding Sites; D004579:Electron Transport; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D006571:Heterocyclic Compounds; D037742:Nanotubes, Carbon; D014867:Water; C063887:tetrathiafulvalene