title: Nanotubular J-aggregates and quantum dots coupled for efficient resonance excitation energy transfer.
abstract: Resonant coupling between distinct excitons in organic supramolecular assemblies and inorganic semiconductors is supposed to offer an approach to optoelectronic devices. Here, we report on colloidal nanohybrids consisting of self-assembled tubular J-aggregates decorated with semiconductor quantum dots (QDs) via electrostatic self-assembly. The role of QDs in the energy transfer process can be switched from a donor to an acceptor by tuning its size and thereby the excitonic transition energy while keeping the chemistry unaltered. QDs are located within a close distance (<4 nm) to the J-aggregate surface, without harming the tubular structures and optical properties of J-aggregates. The close proximity of J-aggregates and QDs allows the strong excitation energy transfer coupling, which is around 92% in the case of energy transfer from the QD donor to the J-aggregate acceptor and approximately 20% in the reverse case. This system provides a model of an organic-inorganic light-harvesting complex using methods of self-assembly in aqueous solution, and it highlights a route toward hierarchical synthesis of structurally well-defined supramolecular objects with advanced functionality.
authors.affiliation: Department of Physics, Humboldt-Universität zu Berlin , Newtonstr 15, 12489 Berlin, Germany.
authors.forename: Yan
authors.initials: Y
authors.lastname: Qiao
authors.forename: Frank
authors.initials: F
authors.lastname: Polzer
authors.forename: Holm
authors.initials: H
authors.lastname: Kirmse
authors.forename: Egon
authors.initials: E
authors.lastname: Steeg
authors.forename: Sergei
authors.initials: S
authors.lastname: Kühn
authors.forename: Sebastian
authors.initials: S
authors.lastname: Friede
authors.forename: Stefan
authors.initials: S
authors.lastname: Kirstein
authors.forename: Jürgen P
authors.initials: JP
authors.lastname: Rabe
mesh_terms: D031541:Fluorescence Resonance Energy Transfer; D008958:Models, Molecular; D008968:Molecular Conformation; D045663:Quantum Dots / Q000737:chemistry*; D012666:Semiconductors; D013499:Surface Properties
keywords: CdTe; Förster resonance energy transfer (FRET); amphiphilic cyanine dye; light harvesting; organic−inorganic hybrid system; self-assembly; semiconductor