Advanced Materials

Cover image for Vol. 14 Issue 13‐14

July, 2002

Volume 14, Issue 13-14

Pages 939–1006

    1. Contents: Adv. Mater. 13-14/2002 (pages 939–942)

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<939::AID-ADMA939>3.0.CO;2-D

    2. Contents: Chem. Vap. Deposition 4/2002 (pages 945–946)

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<945::AID-ADMA945>3.0.CO;2-P

    3. You have free access to this content
      In Profile: Andrew R. Barron (page 947)

      Version of Record online: 12 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<947::AID-ADMA947>3.0.CO;2-H

    4. The Shift from “Hard” to “Soft” Electronics (pages 949–952)

      T. Tsutsui and K. Fujita

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<949::AID-ADMA949>3.0.CO;2-9

      Organic electronics have emerged as a promising new technology, with likely applications in areas such as flexible displays and electronic labels. This is reflected in a shift in research and development efforts from traditional hard materials such as silicon to soft, organic materials. In this essay, the significant breakthroughs achieved in this field over the last 50 years are summarized and the major differences between hard and soft electronics are highlighted. It is envisaged that organic electronics will play an important role in the 21st century.

    5. Manipulating and Monitoring Biomolecular Interactions with Conducting Electroactive Polymers (pages 953–960)

      G.G. Wallace and L.A.P. Kane-Maguire

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<953::AID-ADMA953>3.0.CO;2-T

      Biointeractions with for instance amino acids and DNA can be monitored and regulated using conductive electroactive polymers. This article describes several of these biointeractions and the effect of doping on them. The progress in practical applications and simple device fabrication is also mentioned. The Figure shows an optical micrograph of living (healthy) red blood cells incorporated into a conducting polymer during polymerization.

    6. Morphology and Thermal Stability of Metal Contacts on Crystalline Organic Thin Films (pages 961–963)

      A.C. Dürr, F. Schreiber, M. Kelsch, H.D. Carstanjen and H. Dosch

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<961::AID-ADMA961>3.0.CO;2-X

      The interfacial properties of metal contacts on organic substrates are strongly determined by the preparation conditions of the gold film. A gold–diindenoperylene (DIP) interface has been studied as a model system for metal contacts on organic electronic devices. The Figure juxtaposes the two deposition methods used, whereby only the first method leads to a well-defined interface with only a slight amount of diffusion of the gold film into the DIP layer.

    7. A Novel Conductive Polymer–Sulfur Composite Cathode Material for Rechargeable Lithium Batteries (pages 963–965)

      J. Wang, J. Yang, J. Xie and N. Xu

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<963::AID-ADMA963>3.0.CO;2-P

      Conductive polymersulfur composites have been reported as potential cathode materials for rechargeable batteries due to their structure, i.e., sulfur embedded in a conductive polymer host at molecular level (see Figure for a backscattered electron photograph). The low-cost, environmentally friendly sulfur composite has outstanding electrochemical properties and is, hence, a highly interesting material for the next generation of lithium batteries.

    8. A New Approach to Chemosensors for Anions Using MCM-41 Grafted with Amino Groups (pages 966–969)

      A.B. Descalzo, D. Jimenez, M.D. Marcos, R. Martínez-Máñez, J. Soto, J. El Haskouri, C. Guillém, D. Beltrán, P. Amorós and M.V. Borrachero

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<966::AID-ADMA966>3.0.CO;2-D

      Use of functionalized MCM-41 solids as anion sensing systems has been demonstrated for the first time. The combination of the binding properties of molecular receptors with the structural characteristics of solid, inorganic surfaces leads to remarkably enhanced anion sensing response. The Figure shows a schematic view of a solid surface, with 300 Å diameter holes that are filled with aminoanthracene molecules.

    9. Morphosynthesis of Organoclay Microspheres with Sponge-like or Hollow Interiors (pages 969–972)

      E. Muthusamy, D. Walsh and S. Mann

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<969::AID-ADMA969>3.0.CO;2-1

      Organoclay hollow microspheres (see Figure) and spheroids with foam-like interiors have been prepared by an in-situ reaction in water-in-oil emulsion droplets. The materials could be calcined at 673 K with retention of the morphology, thus proving the thermal stability. The technique should be applicable to a wide range of organo-functionalized clay materials, which may be used in, e.g., controlled release processes.

    10. Micropore Development and Structure Rearrangement of Single-Wall Carbon Nanohorn Assemblies by Compression (pages 973–975)

      E. Bekyarova, K. Kaneko, M. Yudasaka, K. Murata, D. Kasuya and S. Iijima

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<973::AID-ADMA973>3.0.CO;2-L

      Mesopores become micropores under pressure (10–50 MPa), which is applied to dahlia-shaped arrays of single-wall carbon nanohorns (SWNHs, see Figure for a TEM image) in liquid media, such as ethanol or glycerol. While the morphology of the arrays does not substantially change, the apparent volume shrinks by a factor of 20 and micropores develop. An improved procedure may even provide a route to supercritical gas absorbers.

    11. Green Phosphorescent Dendrimer for Light-Emitting Diodes (pages 975–979)

      S.-C. Lo, N.A.H. Male, J.P.J. Markham, S.W. Magennis, P.L. Burn, O.V. Salata and I.D.W. Samuel

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<975::AID-ADMA975>3.0.CO;2-D

      Highly efficient organic LEDs made by solution processing are reported. It is shown that the dendritic architecture (see Figure) can be used to solubilize luminescent chromophores and form uniform films of blends. The simple device structures containing a light-emitting chromophore are amongst the most efficient solution-processed devices reported. Thanks to this technique, the inkjet printing of phosphorescent materials becomes feasible.

    12. Orienting Eu(dnm)3phen by Tensile Drawing in Polyethylene: Polarized Eu3+ Emission (pages 980–983)

      C.Y. Yang, V. Srdanov, M.R. Robinson, G.C. Bazan and A.J. Heeger

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<980::AID-ADMA980>3.0.CO;2-T

      Uniaxial orientation of metalorganic europium complexes (see Figure) has been achieved using ultra-high molecular weight polyethylene. The orientation of the ligand molecules results in the transfer of polarized energy from the ligand to Eu3+, and thus yields polarized emission from the complex. The spectral properties as well as the crystallographic details of the complexes are described in detail.

    13. Unusual Characteristics of Diffraction Gratings in a Liquid Crystal Cell (pages 983–988)

      B.J. Kim, S.-D. Lee, S.Y. Park and D.H. Choi

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<983::AID-ADMA983>3.0.CO;2-H

      Induced liquid crystal gratings using an azo-polymer as an alignment layer in the cell provide an interesting possibility for storing information. Here a polarization grating and azobenzene reorientation are exploited to enhance the gain effect and the stability of the diffraction efficiency by manipulating the pump beams. The Figure juxtaposes an original image and its holographic reconstruction using the described procedure.

    14. A Novel Charge Transport Material Fabricated Using a Liquid Crystalline Semiconductor and Crosslinked Polymer (pages 988–991)

      N. Yoshimoto and J. Hanna

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<988::AID-ADMA988>3.0.CO;2-Y

      A hybrid material with high electronic conduction has been fabricated by photo-polymerization of the liquid crystalline semiconductor 2-(4′-octylphenyl)-6-dodecyloxynaphthalene (8-PNP-O12, see Figure for micrographic texture) and a crosslinked monomer. The charge-transport properties and liquid crystalline behavior are investigated and shown to be promising for device applications.

    15. Growth of GaN Nanorods by a Hydride Vapor Phase Epitaxy Method (pages 991–993)

      H.-M. Kim, D.S. Kim, Y.S. Park, D.Y. Kim, T.W. Kang and K.S. Chung

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<991::AID-ADMA991>3.0.CO;2-L

      Straight and well-aligned GaN nanorods have been obtained by horizontal hydride vapor phase epitaxy (HVPE) at a relatively low temperature (∼ 480 °C). This catalyst- and template- independent method involves the controllable growth of GaN nanorods on a sapphire substrate, with the rods preferentially oriented along the crystal c-axis. The Figure shows a cross-sectional SEM image of the GaN nanorods.

    16. Self-Supporting Porous Zeolite Membranes with Sponge-like Architecture and Zeolitic Microtubes (pages 994–997)

      Y. Wang, Y. Tang, A. Dong, X. Wang, N. Ren, W. Shan and Z. Gao

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<994::AID-ADMA994>3.0.CO;2-9

      Self-supported porous zeolite membranes have been prepared in a simple but effective way using cellulose acetate membranes as templates. The spongy zeolite membranes possess unique ramified pore structures in three levels (see Figure), i.e., interconnected micrometer-sized macropores among the zeolitic microtubes, channel-like submicrometer-sized pores inside the microtubes, and zeolite micropores (< 1 nm) on microtube walls.

    17. Carbon Nanotube Films for Damping Applications (pages 997–1000)

      N. Koratkar, B.Q. Wei and P.M. Ajayan

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<997::AID-ADMA997>3.0.CO;2-Y

      Carbon nanotube films that are mechanically robust and light weight (see Figure) have been engineered to coat surfaces of metallic structures or to be embedded within composite/heterogeneous systems. For high-temperature applications the performance of the nanotube films is expected to be superior to conventional damping treatments using structures made of viscoelastic materials.

    18. Laser Writing in Polarized Silver Nanorod Films (pages 1000–1004)

      O. Wilson, G.J. Wilson and P. Mulvaney

      Version of Record online: 1 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<1000::AID-ADMA1000>3.0.CO;2-E

      Polarized images have been prepared using simple laser-induced melting of aligned nanorods in a polymer film. The technique is easy-to-use, cost-effective, and may be used to render the read-out either legible or illegible (see Figure). The information content could be increased by creating ordered nanoparticles with different angles of polarization, thereby permitting readout from different layers within the film, which might lead to 3D applications.

    19. Book Review: The Atomistic Nature of Crystal Growth. By B. Mutavtschiev (Ed.) (page 1005)

      G. Horowitz

      Version of Record online: 11 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<1005::AID-ADMA1005>3.0.CO;2-L

    20. Book Review: Modeling Materials Processing. By Jonathan A. Dantzig, Charles L. Tucker III (pages 1005–1006)

      D. Raabe

      Version of Record online: 11 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<1005::AID-ADMA11111005>3.0.CO;2-D

    21. Book Review: Metal Nanoparticles. By Daniel L. Feldheim, Colby A. Foss, Jr. (Eds.) (page 1006)

      J. H. Fendler

      Version of Record online: 11 JUL 2002 | DOI: 10.1002/1521-4095(20020705)14:13/14<1006::AID-ADMA1006>3.0.CO;2-F