Advanced Materials

Cover image for Vol. 18 Issue 21

November, 2006

Volume 18, Issue 21

Pages 2795–2916

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
    1. Cover Picture: Metal–Silica Hybrid Nanostructures for Surface-Enhanced Raman Spectroscopy (Adv. Mater. 21/2006)

      M. Schierhorn, S. J. Lee, S. W. Boettcher, G. D. Stucky and M. Moskovits

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200690088

      The preparation of surface-enhanced Raman spectroscopy (SERS)-active substrates consisting of an ordered array of silver-tipped silica nanorods is reported (see figure and cover). Signal intensities obtained from test molecules are enhanced by factors of 10–20 for measurements on substrates consisting of small aggregates as compared to arrays of single particles. The reduced silver surface area of the hybrid system compared to other substrates is important to minimize the quantity of analyte necessary for detection.

  2. Inside Front Cover

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
    1. Inside Front Cover: Buckled and Wavy Ribbons of GaAs for High-Performance Electronics on Elastomeric Substrates (Adv. Mater. 21/2006)

      Y. Sun, V. Kumar, I. Adesida and J. A. Rogers

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200690089

      Single-crystalline GaAs ribbons with thicknesses in the sub-micrometer range are fabricated with well-defined “wavy” (top) and “buckled” (bottom) geometries (see figure and inside cover). The resulting structures, on the surface of or embedded in an elastomeric substrate, exhibit reversible stretchability and compressibility to strains >10%, more than five times larger than that of GaAs itself. By integrating ohmic and Schottky contacts, high-performance stretchable electronic devices (e.g., metal semiconductor field-effect transistors) can be achieved.

  3. Contents

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
  4. Corrections

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
    1. You have free access to this content
      Angle-Dependent Extinction of Anisotropic Silica/Au Core/Shell Colloids Made via Ion Irradiation (page 2802)

      J. J. Penninkhof, C. Graf, T. van Dillen, A. M. Vredenberg, A. van Blaaderen and A. Polman

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200690085

      This article corrects:

      Angle-Dependent Extinction of Anisotropic Silica/Au Core/Shell Colloids Made via Ion Irradiation1

      Vol. 17, Issue 12, 1484–1488, Version of Record online: 7 JUN 2005

    2. You have free access to this content
      Reversible Formation of Molecular Junctions in 2D Nanoparticle Arrays (page 2803)

      J. Liao, L. Bernard, M. Langer, C. Schönenberger and M. Calame

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200690086

      This article corrects:

      Reversible Formation of Molecular Junctions in 2D Nanoparticle Arrays1

      Vol. 18, Issue 18, 2444–2447, Version of Record online: 12 SEP 2006

  5. Correspondence

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
  6. Review

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
    1. Protonated Titanates and TiO2 Nanostructured Materials: Synthesis, Properties, and Applications (pages 2807–2824)

      D. V. Bavykin, J. M. Friedrich and F. C. Walsh

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200502696

      Thumbnail image of graphical abstract

      The synthesis of tubular and fibrous nanostructures of titanates and TiO2, their structure, physiochemical properties, potential applications and stability are considered. Early applications of nanostructured titanates (see figure) have taken place in the fields of catalysis, photocatalysis, electrocatalysis, lithium batteries, hydrogen storage, and solar cells.

  7. Communications

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index
    1. High-Density Arrays of Platinum Nanostructures and Their Hierarchical Patterns (pages 2825–2828)

      U-H. Lee, J. H. Lee, D.-Y. Jung and Y.-U. Kwon

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200600271

      Thumbnail image of graphical abstract

      Mesoporous silica templates combined with fast electrochemical deposition provides a means to grow arrays of nanorods 9 nm in diameter and with variable lengths up to a few hundreds of nanometers (see figure). Hierarchical nanostructures of Pt arrays with microscale patterns can be obtained by microcontact printing on the mesoporous silica films.

    2. Metal–Silica Hybrid Nanostructures for Surface-Enhanced Raman Spectroscopy (pages 2829–2832)

      M. Schierhorn, S. J. Lee, S. W. Boettcher, G. D. Stucky and M. Moskovits

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200601254

      Thumbnail image of graphical abstract

      The preparation of surface-enhanced Raman spectroscopy (SERS)-active substrates consisting of an ordered array of silver-tipped silica nanorods is reported (see figure and cover). Signal intensities obtained from test molecules are enhanced by factors of 10–20 for measurements on substrates consisting of small aggregates as compared to arrays of single particles. The reduced silver surface area of the hybrid system compared to other substrates is important to minimize the quantity of analyte necessary for detection.

    3. Heteroepitaxial Growth of High-Quality GaN Thin Films on Si Substrates Coated with Self-Assembled Sub-micrometer-sized Silica Balls (pages 2833–2836)

      S. J. An, Y. J. Hong, G.-C. Yi, Y.-J. Kim and D. K. Lee

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200601628

      Thumbnail image of graphical abstract

      Monodisperse sub-micrometer-sized silica balls are employed as an intermediate layer for the heteroepitaxial growth of GaN thin films on Si(111) substrates (see figure). The structural and optical characteristics of the films are shown to be improved compared to conventional techniques, as the maskless overgrowth technique employed simplifies the growth process. This method could be exploited to grow other heteroepitaxial films on substrates with large lattice constants and thermal expansion coefficient mismatches.

    4. Carbon Nanotube Networks: Sensing of Distributed Strain and Damage for Life Prediction and Self Healing (pages 2837–2841)

      E. T. Thostenson and T.-W. Chou

      Version of Record online: 2 OCT 2006 | DOI: 10.1002/adma.200600977

      Thumbnail image of graphical abstract

      Conducting carbon nanotube networks formed in an epoxy polymer matrix can be utilized as highly sensitive in situ sensors for detecting the onset, nature, and evolution of damage in advanced polymer-based composites using direct-current measurements (see figure). These results hold promise for evaluation of autonomic self-healing approaches for polymers and for the development of enhanced life-prediction methodologies.

    5. Self-Assembly of Copper Acetylide Molecules into Extremely Thin Nanowires and Nanocables (pages 2842–2846)

      K. Judai, J. Nishijo and N. Nishi

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600771

      Thumbnail image of graphical abstract

      Copper acetylide molecules self-assemble into nanowires. Subsequent annealing of the C2Cu2 is shown to produce ultrathin copper wire cores encapsulated in carbon outer layers (nanocables, see figure) through the segregation of the elements. The synthesis is so simple that self-assembled acetylide molecules may provide the most cost-effective production of semiconducting nanowires and thin metallic nanowires.

    6. Unveiling the Sliding Motion in Topological Networks: Influence of the Swelling Solvent on the Relaxation Dynamics (pages 2847–2851)

      G. Fleury, G. Schlatter, C. Brochon and G. Hadziioannou

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200600107

      Thumbnail image of graphical abstract

      Supramolecular sliding gels show specific viscoelastic behavior strongly dependent on the swelling solvent. The gels that are swollen in H2O possess highly crosslinked domains connected by short flexible strands, whereas in DMSO the network strands are long and rigid because of the presence of transient physical tubes. Furthermore, the mechanical behavior in DMSO corresponds to a simple Zener model, underlining the high relaxation ability with a single relaxation time.

      Corrected by:

      Correction: Unveiling the Sliding Motion in Topological Networks: Influence of the Swelling Solvent on the Relaxation Dynamics

      Vol. 18, Issue 24, 3199, Version of Record online: 18 DEC 2006

    7. Weak Ferromagnetism and Dynamic Magnetic Behavior in a Single End-to-End Azide-Bridged Nickel(II) Chain (pages 2852–2856)

      X.-T. Liu, X.-Y. Wang, W.-X. Zhang, P. Cui and S. Gao

      Version of Record online: 2 OCT 2006 | DOI: 10.1002/adma.200600253

      Thumbnail image of graphical abstract

      An isolated 1D NiIIchain containing single end-to-end azide bridges has been constructed (see figure). The non-centrosymmetric character of the three-atom single-bridge leads to a weak ferromagnetic behavior. Surprisingly, it shows a strong frequency dependence of AC susceptibility and magnetic hysteresis loops even at 10 K.

    8. Buckled and Wavy Ribbons of GaAs for High-Performance Electronics on Elastomeric Substrates (pages 2857–2862)

      Y. Sun, V. Kumar, I. Adesida and J. A. Rogers

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600646

      Thumbnail image of graphical abstract

      Single-crystalline GaAs ribbons with thicknesses in the sub-micrometer range are fabricated with well-defined “wavy” (top) and “buckled” (bottom) geometries (see figure and inside cover). The resulting structures, on the surface of or embedded in an elastomeric substrate, exhibit reversible stretchability and compressibility to strains >10%, more than five times larger than that of GaAs itself. By integrating ohmic and Schottky contacts, high-performance stretchable electronic devices (e.g., metal semiconductor field-effect transistors) can be achieved.

    9. Long-Range-Ordered, Molecular-Induced Nanofaceting (pages 2863–2867)

      M. Fanetti, L. Gavioli and M. Sancrotti

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600510

      Thumbnail image of graphical abstract

      Ordered molecular nanostructured films (see figure) are obtained by exploiting the molecular-induced substrate faceting transition, following a very simple protocol. The obtained nanostructures show univocal alignment and quite good homogeneity, and the pattern periodicity can be controlled in the process. The stepped structure of the vicinal metallic substrate has a key role in the film production mechanism.

    10. Composite Nanocapsules: Lipid Vesicles Covered with Several Layers of Crosslinked Polyelectrolytes (pages 2868–2871)

      M. Germain, S. Grube, V. Carriere, H. Richard-Foy, M. Winterhalter and D. Fournier

      Version of Record online: 5 OCT 2006 | DOI: 10.1002/adma.200600860

      Thumbnail image of graphical abstract

      Biologically active proteins are loaded into liposomes, which are then used as templates for the layer-by-layer deposition of polyelectrolytes. The multilayer polyelectrolyte layers are then crosslinked to form a robust protective barrier (see figure). Enzymes encapsulated within composite nanocapsules generated by this procedure are able to retain their substrate selectivity and activity even in the presence of detergent, suggesting the potential use of these structures as nanoreactors.

    11. Efficient Vacuum-Deposited Organic Solar Cells Based on a New Low-Bandgap Oligothiophene and Fullerene C60 (pages 2872–2875)

      K. Schulze, C. Uhrich, R. Schüppel, K. Leo, M. Pfeiffer, E. Brier, E. Reinold and P. Bäuerle

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600658

      Thumbnail image of graphical abstract

      Organic solar cells based on a new oligothiophene derivative (see figure) and fullerene C60 exhibit power efficiencies of up to 3.4 %. α,α′-Bis(2,2-dicyanovinyl)-quinquethiophene (DCV5T) features a reduced optical gap with high absorption coefficients between 450 and 650 nm. Dicyanovinyl substituents on the oligothiophene rings lower the bandgap and increase the ionization energy of these oligomers, enabling the formation of photoactive heterojunctions with C60 and yielding open-circuit photovoltages as high as 1 V.

    12. Direct Laser Writing of Microtunnels and Reservoirs on Nanocomposite Materials (pages 2876–2879)

      H. Chen, X. Liu, H. Muthuraman, J. Zou, J. Wang, Q. Dai and Q. Huo

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200601560

      Thumbnail image of graphical abstract

      Using the efficient photon–thermal energy conversion property of gold nanoparticles, a direct laser writing method has been developed for the fabrication of microstructures including microtunnels (see figure), holes, and reservoirs on nanoparticle/polymer composite thin films. The microstructures are formed by a subsurface layer explosion that occurs in the nanocomposite film as a result of the thermal decomposition of the polymer.

    13. Strong Electroluminescence from Polymer Films with Heavily Quenched Photoluminescence (pages 2880–2883)

      Y. Hu, Y. Zhang and J. Gao

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200600090

      Thumbnail image of graphical abstract

      Strong electroluminescence (see figure) is observed for polymer films that are electrochemically doped in situ and whose photoluminescence is initially close to 100 % quenched. The mechanisms behind this phenomenon and its implications for device applications are explored.

    14. High Photovoltaic Performance of a Low-Bandgap Polymer (pages 2884–2889)

      D. Mühlbacher, M. Scharber, M. Morana, Z. Zhu, D. Waller, R. Gaudiana and C. Brabec

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600160

      Thumbnail image of graphical abstract

      Bulk heterojunction polymer solar cells made from a novel low-bandgap polymer show the highest photocurrent response so far for this class of materials (see figure). Efficiencies up to 3.2 % are realized, but this conjugated polymer has the intrinsic capability to reach 7 % efficiency because of its material properties. Possible loss mechanisms and improvements are discussed.

      Corrected by:

      Correction: High Photovoltaic Performance of a Low-Bandgap Polymer

      Vol. 18, Issue 22, 2931, Version of Record online: 14 NOV 2006

    15. GdIII-Functionalized Fluorescent Quantum Dots as Multimodal Imaging Probes (pages 2890–2894)

      H. Yang, S. Santra, G. A. Walter and P. H. Holloway

      Version of Record online: 5 OCT 2006 | DOI: 10.1002/adma.200502665

      Thumbnail image of graphical abstract

      Multimodal probes of GdIII-functionalized silica-coated CdS:Mn/ZnS quantum dots (see figure) that exhibit yellow fluorescence and strong paramagnetism are reported. High magnetic resonance imaging (MRI) contrast is exhibited by these quantum dots. These properties make for a probe that can operate in multiple modes, which is highly desirable for in vivo bioimaging applications.

    16. Freestanding 2D Arrays of Silver Nanorods (pages 2895–2899)

      R. Gunawidjaja, C. Jiang, H. Ko and V. V. Tsukruk

      Version of Record online: 10 OCT 2006 | DOI: 10.1002/adma.200600540

      Thumbnail image of graphical abstract

      Freestanding silver nanorods (Ag-NWs) sandwiched between poly(allyamine hydrochloride)/polystyrene sulfonate polyelectrolyte bilayers, (PAH/PSS)10PAHAg(PAH/PSS)10PAH, and suspended over a 150 μm opening (see figure) have been prepared. At a Ag-NW volume fraction of 22.5%, the membrane is both mechanically robust and electrically conductive.

    17. Surface-Induced Self-Encapsulation of Polymer Thin-Film Transistors (pages 2900–2904)

      A. C. Arias, F. Endicott and R. A. Street

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200600623

      Thumbnail image of graphical abstract

      Surface-induced phase separation in polymer blends is used to fabricate self-encapsulated thin-film transistors. The semiconductor material preferentially wets the gate dielectric surface and a self-organized bilayer of two polymers phases occurs spontaneously (see figure). The encapsulant and semiconductor are deposited in one step.

    18. Temperature-Controlled Assembly and Release from Polymer Vesicles of Poly(ethylene oxide)-block- poly(N-isopropylacrylamide) (pages 2905–2909)

      S. Qin, Y. Geng, D. E. Discher and S. Yang

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200601019

      Thumbnail image of graphical abstract

      Narrow-dispersity thermoresponsive block copolymers of poly(ethylene oxide)-block-poly(N-isopropylacrylamide) self-assemble into vesicles at temperatures above 32 °C. The vesicles integrate a hydrophobic fluorescent dye into their membranes and encapsulate the hydrophilic anticancer drug doxorubicin. Temperature-controlled release of the dye through disintegration of the vesicles takes place at temperatures below 32 °C, as shown in the figure.

    19. Two-Photon 3D Optical Data Storage via Fluorescence Modulation of an Efficient Fluorene Dye by a Photochromic Diarylethene (pages 2910–2914)

      C. C. Corredor, Z.-L. Huang and K. D. Belfield

      Version of Record online: 30 OCT 2006 | DOI: 10.1002/adma.200600826

      Thumbnail image of graphical abstract

      A two-photon 3D optical storage system based on a photochromic diarylethene (1,2-bis(2-methylbenzo[b]thiophen-3-yl)hexafluorocyclopentene) and a highly efficient two-photon absorbing fluorescent dye (2,7-bis[4-(9,9-didecylfluoren-2-yl)vinyl]phenylbenzothiazole) is demonstrated. The figure shows two-photon fluorescent readout of data recorded by single-photon excitation. The system is suitable for recording data in thick storage media and providing a non-destructive readout method.

  8. Index

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Contents
    5. Corrections
    6. Correspondence
    7. Review
    8. Communications
    9. Index

SEARCH

SEARCH BY CITATION