title: Towards Organized Hybrid Nanomaterials at the Air/Water Interface Based on Liquid-Crystal/ZnO Nanocrystals.
abstract: The ability to self-assemble nanosized ligand-stabilized metal oxide or semiconductor materials offers an intriguing route to engineer nanomaterials with new tailored properties from the disparate components. We describe a novel one-pot two-step organometallic approach to prepare ZnO nanocrystals (NCs) coated with deprotonated 4-(dodecyloxy)benzoic acid (i.e., an X-type liquid-crystalline ligand) as a model LC system (termed ZnO-LC1 NCs). Langmuir and Langmuir-Blodgett films of the resulting hybrids are investigated. The observed behavior of the ZnO NCs at the air/water interface is rationalized by invoking a ZnO-interdigitation process mediated by the anchored liquid-crystalline shell. The ordered superstructures form according to mechanism based on a ZnO-interdigitation process mediated by liquid crystals (termed ZIP-LC). The external and directed force applied upon compression at the air/water interface and the packing of the ligands that stabilize the ZnO cores drives the formation of nanorods of ordered internal structure. To study the process in detail, we follow a nontraditional protocol of thin-film investigation. We collect the films from the air/water interface in powder form (ZnO-LC1 LB), resuspend the powder in organic solvents and utilize otherwise unavailable experimental techniques. The structural and physical properties of the resulting superlattices were studied by using electron microscopy, atomic force microscopy, X-ray studies, dynamic light scattering, thermogravimetric analysis, UV/Vis absorption, and photoluminescence spectroscopy.
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland). jpaczesny@ichf.edu.pl.
authors.forename: Jan
authors.initials: J
authors.lastname: Paczesny
authors.affiliation: Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw (Poland).
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Wolska-Pietkiewicz
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland).|Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw (Poland).
authors.forename: Ilona
authors.initials: I
authors.lastname: Binkiewicz
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland).
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Wróbel
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland).
authors.forename: Monika
authors.initials: M
authors.lastname: Wadowska
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland).
authors.forename: Kinga
authors.initials: K
authors.lastname: Matuła
authors.affiliation: Institute of High Pressure Physics, UNIPRESS, Polish Academy of Sciences, Sokołowska 29/37, 01-142 Warsaw (Poland).
authors.forename: Igor
authors.initials: I
authors.lastname: Dzięcielewski
authors.affiliation: Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw (Poland).
authors.forename: Damian
authors.initials: D
authors.lastname: Pociecha
authors.affiliation: Institute of High Pressure Physics, UNIPRESS, Polish Academy of Sciences, Sokołowska 29/37, 01-142 Warsaw (Poland).
authors.forename: Julita
authors.initials: J
authors.lastname: Smalc-Koziorowska
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland). lewin@ch.pw.edu.pl.|Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw (Poland). lewin@ch.pw.edu.pl.
authors.forename: Janusz
authors.initials: J
authors.lastname: Lewiński
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland). rholyst@ichf.edu.pl.
authors.forename: Robert
authors.initials: R
authors.lastname: Hołyst
keywords: Langmuir-Blodgett films; ZnO nanocrystals; liquid crystals; nanomaterials; superlattices; surfaces and interfaces; thin films