Advanced Materials

Cover image for Advanced Materials

February, 2004

Volume 16, Issue 4

Pages 283–370

    1. Contents: Adv. Mater. 4/2004 (pages 283–290)

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200490008

    2. Magnetic Ceramic Films from a Metallopolymer Resist Using Reactive Ion Etching in a Secondary Magnetic Field (pages 291–296)

      S. B. Clendenning, S. Han, N. Coombs, C. Paquet, M. S. Rayat, D. Grozea, P. M. Brodersen, R. N. S. Sodhi, C. M. Yip, Z.-H. Lu and I. Manners

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306262

      Magnetic ceramic films containing metal-rich nanoworm reticulations 200–550 nm wide have been fabricated from a highly metallized metallopolymer resist (see Figure) using oxygen or hydrogen plasma reactive ion etching in a secondary magnetic field. Applications may be found in spintronics and logic circuits.

    3. Tuning Polymer Nanocomposite Morphology: AC Electric Field Manipulation of Epoxy–Montmorillonite (Clay) Suspensions (pages 297–302)

      H. Koerner, J. D. Jacobs, D. W. Tomlin, J. D. Busbee and R. A. Vaia

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306039

      AC electric field alignment (see Figure) offers a route to composite films with unusual physical properties, in numerous geometries and applicable to a wide range of organically modified layered silicates. Exchangeable organic cations on the aluminosilicate surface are suspected to cause the induced dipole. Orientational, compositional, and translational control of nanoparticles, paralleling efforts in electric field-trapping and traveling wave applications, could be achieved.

    4. Facile Creation of a Super-Amphiphobic Coating Surface with Bionic Microstructure (pages 302–305)

      Q. Xie, J. Xu, L. Feng, L. Jiang, W. Tang, X. Luo and C. C. Han

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306281

      A super-amphiphobic polymeric coating, i.e., one that shows both water- and oil-repellent properties, produced by a simple, one-step casting process from two common polymers, is described. The micro–nano binary structure of the film has similarities to that of a lotus leaf. The Figure shows a water droplet on the coating surface, demonstrating a contact angle (CA) of 166 °C.

    5. Hydrogel Nanoparticle Dispersions with Inverse Thermoreversible Gelation (pages 305–309)

      Z. Hu and X. Xia

      Version of Record online: 13 JAN 2004 | DOI: 10.1002/adma.200305560

      A novel aqueous solution of hydrogel nanoparticles with interpenetrating polymer networks of poly(isopropylacrylamide) and poly(acrylic acid) has been synthesized. This hydrogel can form a physically bonded nanoparticle network above a certain gelation temperature. The system exhibits a very rich phase behavior, including a colloidal crystalline phase, in which the system displays iridescent colors (for examples, see Figure).

    6. Adsorption and Self-Assembly of C70 Molecules at the Au(111)/n-Tetradecane Interface: A Scanning Tunneling Microscopy Study (pages 309–312)

      N. Katsonis, A. Marchenko and D. Fichou

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200305774

      An STM study of C70 (sub-)monolayers deposited at an n-tetradecane/Au(111) interface (see Figure) is reported. The adsorption of C70 and C60 are compared in the light of their geometric and electronic differences. While C60 is a strained spherical cage, C70 has a reduced symmetry and an ellipsoidal shape. The structural differences between the C60 and C70 (sub-)monolayers are discussed in terms of commensurability between the adsorbate and the Au (111) lattices.

    7. Transparent Organic Thin-Film Transistor with a Laterally Grown Non-Planar Phthalocyanine Channel (pages 312–316)

      H. Ohta, T. Kambayashi, K. Nomura, M. Hirano, K. Ishikawa, H. Takezoe and H. Hosono

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306015

      An improved-performance transparent organic thin-film transistor (OTFT) is described, which has a vanadyl-phthalocyanine (VOPc) film as an active p-channel, lattice-matched (Sc0.7Y0.3)2O3 film as a high-k gate dielectric, and atomically flat indium tin oxide (ITO) film as the bottom contact (see Figure). These features—lattice matching and atomic flatness—are expected to lead to further improvements in transparent OTFTs.

    8. A Solid-State Organic Electronic Wettability Switch (pages 316–320)

      J. Isaksson, C. Tengstedt, M. Fahlman, N. Robinson and M. Berggren

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306131

      Solid-state devices based on soluble polymers on a rigid substrate, with the active surface facing the environment, have been designed and characterized. The contact angles and spreading of water droplets can be reversibly controlled by electrochemically reducing or oxidizing a polymer surface (see Figure).

    9. High-Performance Organic Light-Emitting Diodes Using ITO Anodes Grown on Plastic by Room- Temperature Ion-Assisted Deposition (pages 321–324)

      Y. Yang, Q. Huang, A. W. Metz, J. Ni, S. Jin, T. J. Marks, M. E. Madsen, A. DiVenere and S.-T. Ho

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200305727

      Ion-assisted deposition (IAD) was used to deposit smooth, adherent, and electrically/optically high-quality indium tin oxide (ITO) films on glass and plastic substrates at room temperature. These films afforded organic light-emitting diode performance comparable to devices with commercial ITO/glass anodes, indicating that IAD is an attractive technique for low-temperature ITO deposition, especially on plastics (see Figure).

    10. Metallic Conductivity in a Polyoxovanadate Radical Salt of Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF): Synthesis, Structure, and Physical Characterization of β″-(BEDT-TTF)5[H3V10O28]·4H2O (pages 324–327)

      E. Coronado, J. R. Galán-Mascarós, C. Giménez-Saiz, C. J. Gómez-García, E. Martínez-Ferrero, M. Almeida and E. B. Lopes

      Version of Record online: 13 JAN 2004 | DOI: 10.1002/adma.200304773

      The first hybrid radical salt of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) using a polyoxovanadate as the counterion, (BEDT-TTF)5[H3V10O28]·4H2O, has been obtained and characterized. It contains segregated mixed-valence 2D stacks of organic radicals interleaved by anionic layers of [H3V10O28]3– anions (see Figure). This compound exhibits high electrical conductivity at room temperature and metallic behavior down to low temperatures.

    11. Tough Nanostructured Metals at Cryogenic Temperatures (pages 328–331)

      Y. M. Wang, E. Ma, R. Z. Valiev and Y. T. Zhu

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200305679

      Copper, titanium, and iron with grain sizes of the order of 100 nm were prepared by severe plastic deformation. At 77 K these materials offer very high yield strength coupled with high ductility, uniform tensile strains, and long-term stability. These properties demonstrate a nanomaterials advantage for science and engineering endeavors that employ or encounter cryogenic temperatures. The Figure shows ductile deformation in the nanostructured Fe.

    12. Design and Fabrication of BN-Sheathed ZnS Nanoarchitectures (pages 331–334)

      Y.-C. Zhu, Y. Bando and L.-W. Yin

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306366

      An effective route has been developed (see Figure) to fabricate 3D ZnS nanoarchitectures. Twin crystals of ZnS whiskers are first fabricated, onto which nanobranches are grown that are sheathed with BN shells. Arrays of ZnS nanobranches were crystallographically aligned on ZnS twin crystals forming ordered nanoarchitectures. The insulating and protecting sheath of BN was completely coated on the ZnS nanoarchitectures to enhance their stability.

    13. Assembly of Gold Nanoparticles into Fibrous Aggregates Using Thiol-Terminated Gelators (pages 335–338)

      M. Kimura, S. Kobayashi, T. Kuroda, K. Hanabusa and H. Shirai

      Version of Record online: 11 NOV 2003 | DOI: 10.1002/adma.200305804

      Gold nanoparticles are organized into a three-dimensional network structure using a newly designed thiol-terminated organic gelator. Gold nanoparticles have been covalently linked with supramolecular nanoscopic fibers, in which the gelators have been assembled by intermolecular hydrogen bonding. The Figure shows fibrous aggregates of Au nanoparticles in the presence of the new gelator (see also the front cover).

    14. “Non-Fouling” Oligo(ethylene glycol)- Functionalized Polymer Brushes Synthesized by Surface-Initiated Atom Transfer Radical Polymerization (pages 338–341)

      H. Ma, J. Hyun, P. Stiller and A. Chilkoti

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200305830

      The in-situ synthesis of oligo(ethylene glycol)-functionalized polymer brushes from a self-assembled monolayer of an alkanethiol on gold that presents a tethered initiator by surface-initiated atom transfer radical polymerization is reported. These polymer brushes exhibit no detectable adsorption of proteins, and are cell-resistant for up to a month under typical cell culture conditions. The synthesis method is compatible with a range of patterning techniques from the nano- to the microscale, and enables the patterning of cells in a biologically relevant milieu over extended periods of time. Images of the brushes are shown on the inside front cover.

    15. Engineered Planar Defects Embedded in Opals (pages 341–345)

      E. Palacios-Lidón, J. F. Galisteo-López, B. H. Juárez and C. López

      Version of Record online: 30 JAN 2004 | DOI: 10.1002/adma.200306172

      A method for the fabrication of engineered planar defects inside opals (see Figure) is presented. These defects act as photonic microcavities, introducing a localized state in the gap. The scalability of the defect allows for the tuning of the spectral position of the defect by changing the size of the defect relative to the periodicity of the lattice.

    16. Dielectric Planar Defects in Colloidal Photonic Crystal Films (pages 346–349)

      N. Tétreault, A. Mihi, H. Míguez, I. Rodríguez, G. A. Ozin, F. Meseguer and V. Kitaev

      Version of Record online: 30 JAN 2004 | DOI: 10.1002/adma.200306361

      A straightforward synthetic route to produce colloidal photonic crystals containing dielectric planar defects of controlled thickness (see Figure) is presented. Allowed states that arise within the stop band as a result of this doping greatly modify the reflectance properties of the crystals, in good agreement with theoretical predictions.

    17. Coating Carbon Nanotubes with Rare Earth Oxide Multiwalled Nanotubes (pages 350–352)

      L. Fu, Z. M. Liu, Y. Q. Liu, B. X. Han, J. Q. Wang, P. A. Hu, L. C. Cao and D. B. Zhu

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306213

      Using a simple low-temperature chemical-solution method, multi-walled carbon nanotubes (MWCNTs) coated with crystalline multi-walled europium oxide nanotubes have been successfully synthesized (see Figure). The studies conducted show that such MWCNTs provide an opportunity for synthesising various rare earth oxide nanotubes, including non-layered structure compounds, potentially useful for nanoscale optoelectronic devices.

    18. Well-Aligned “Nano-Box-Beams” of SnO2 (pages 353–356)

      Y. Liu, J. Dong and M. Liu

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306104

      A new nanostructure, a “nano-box-beam”, of tin dioxide has been synthesized using a vapor deposition process in open atmosphere (see Figure). Each as-grown SnO2 nanotube is a single crystal with four {110} peripheral surfaces and [001] growth direction. The new nanostructure could be used in devices such as nanobatteries, nanoscale fuel cells, and nanosensors.

    19. Dramatic Enhancement of Photorefractive Properties by Controlling Electron Trap Density in a Monolithic Material (pages 356–360)

      W. You, Z. Hou and L. Yu

      Version of Record online: 13 JAN 2004 | DOI: 10.1002/adma.200306133

      Serving as the electron-trapping center in photorefractive (PR) materials, the molecule M1, having a more electron-deficient core, M, was doped with a monolithic PR material M0 (see Figure). Typical PR properties were dramatically improved with only 0.05 wt.-% M1 with M0. An optical gain of 235 cm–1 at a field of 35 V μm–1 and diffraction efficiency of 77.5 % at a low field of 23 V μm–1 can be obtained.

    20. Electrospinning Nanofibers as Uniaxially Aligned Arrays and Layer-by-Layer Stacked Films (pages 361–366)

      D. Li, Y. Wang and Y. Xia

      Version of Record online: 26 FEB 2004 | DOI: 10.1002/adma.200306226

      Conventional electrospinning has been modified to generate nanofibers as uniaxially aligned arrays. The success of this method was due to a collector composed of two conductive strips separated by an insulating gap of variable width. Direction is imparted by electrostatic interactions. Nanofibers were stacked into multi-layered architectures with controllable hierarchical structures (see Figure).