title: Directed self-assembly in laponite/CdSe/polyaniline nanocomposites.
abstract: Laponite films provide versatile inorganic scaffolds with materials architectures that direct the self-assembly of CdSe quantum dots (QDs or EviTags) and catalytic surfaces that promote the in situ polymerization of polyaniline (PANI) to yield novel nanocomposites for light emitting diodes (LEDs) and solar cell applications. Water-soluble CdSe EviTags with varying, overlapping emission wavelengths in the visible spectrum were incorporated using soft chemistry routes within Na-Laponite host film platforms to achieve broadband emission in the visible spectrum. QD concentrations, composition and synthesis approach were varied to optimize photophysical properties of the films and to mediate self-assembly, optical cascading and energy transfer. In addition, aniline tetramers coupled to CdSe (QD-AT) surfaces using a dithioate linker were embedded within Cu-Laponite nanoscaffolds and electronically coupled to PANI via vapor phase exposure. Nanotethering and specific host-guest and guest-guest interactions that mediate nanocomposite photophysical behavior were probed using electronic absorption and fluorescence spectroscopies, optical microscopy, AFM, SEM, powder XRD, NMR and ATR-FTIR. Morphology studies indicated that Lap/QD-AT films synthesized using mixed solvent, layer by layer (LbL) methods exhibited anisotropic supramolecular structures with unique mesoscopic ordering that affords bifunctional networks to optimize charge transport.
authors.affiliation: Department of Chemistry, Union College, Schenectady, New York 12308, USA. kehlbeck@union.edu
authors.forename: Joanne D
authors.initials: JD
authors.lastname: Kehlbeck
authors.forename: Michael E
authors.initials: ME
authors.lastname: Hagerman
authors.forename: Brian D
authors.initials: BD
authors.lastname: Cohen
authors.forename: Jennifer
authors.initials: J
authors.lastname: Eliseo
authors.forename: Melissa
authors.initials: M
authors.lastname: Fox
authors.forename: William
authors.initials: W
authors.lastname: Hoek
authors.forename: David
authors.initials: D
authors.lastname: Karlin
authors.forename: Evan
authors.initials: E
authors.lastname: Leibner
authors.forename: Emily
authors.initials: E
authors.lastname: Nagle
authors.forename: Michael
authors.initials: M
authors.lastname: Nolan
authors.forename: Ian
authors.initials: I
authors.lastname: Schaefer
authors.forename: Alexandra
authors.initials: A
authors.lastname: Toney
authors.forename: Michael
authors.initials: M
authors.lastname: Topka
authors.forename: Richard
authors.initials: R
authors.lastname: Uluski
authors.forename: Charles
authors.initials: C
authors.lastname: Wood
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D019187:Cadmium Compounds / Q000737:chemistry*; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D010777:Photochemistry / Q000379:methods; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D000814:Aniline Compounds; D019187:Cadmium Compounds; D018036:Selenium Compounds; D017640:Silicates; C416807:polyaniline; C058667:cadmium selenide; C524813:laponite