title: Acentric 2-D ensembles of D-br-A electron-transfer chromophores via vectorial orientation within amphiphilic n-helix bundle peptides for photovoltaic device applications.
abstract: We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor-bridge-acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle's interior is shown to provide a unique solvation environment for the D-br-A assembly not accessible in conventional solvents and thereby control the magnitudes of both light-induced ET and thermal charge recombination rate constants. The amphiphilicity of the bundle's exterior was employed to vectorially orient the peptide-chromophore complex at a liquid-gas interface, and its ends were tailored for subsequent covalent attachment to an inorganic surface, via a "directed assembly" approach. Structural data, combined with evaluation of the excited state dynamics exhibited by these peptide-chromophore complexes, demonstrate that densely packed, acentrically ordered 2-D monolayer ensembles of such complexes at high in-plane chromophore densities approaching 1/200 Å(2) offer unique potential as active layers in binary heterojunction photovoltaic devices.
authors.affiliation: Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
authors.forename: Jaseung
authors.initials: J
authors.lastname: Koo
authors.forename: Jaehong
authors.initials: J
authors.lastname: Park
authors.forename: Andrey
authors.initials: A
authors.lastname: Tronin
authors.forename: Ruili
authors.initials: R
authors.lastname: Zhang
authors.forename: Venkata
authors.initials: V
authors.lastname: Krishnan
authors.forename: Joseph
authors.initials: J
authors.lastname: Strzalka
authors.forename: Ivan
authors.initials: I
authors.lastname: Kuzmenko
authors.forename: H Christopher
authors.initials: HC
authors.lastname: Fry
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Therien
authors.forename: J Kent
authors.initials: JK
authors.lastname: Blasie
mesh_terms: D004579:Electron Transport; D049329:Nanostructures / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary
chemical_list: D010455:Peptides