Directed self-assembly in laponite/CdSe/polyaniline nanocomposites.
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.
Kehlbeck
Joanne D
JD
Department of Chemistry, Union College, Schenectady, New York 12308, USA. kehlbeck@union.edu
Hagerman
Michael E
ME
Cohen
Brian D
BD
Eliseo
Jennifer
J
Fox
Melissa
M
Hoek
William
W
Karlin
David
D
Leibner
Evan
E
Nagle
Emily
E
Nolan
Michael
M
Schaefer
Ian
I
Toney
Alexandra
A
Topka
Michael
M
Uluski
Richard
R
Wood
Charles
C
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
D000814:Aniline Compounds; D019187:Cadmium Compounds; D018036:Selenium Compounds; D017640:Silicates; C416807:polyaniline; C058667:cadmium selenide; C524813:laponite