Advanced Functional Materials

Cover image for Vol. 16 Issue 11

July, 2006

Volume 16, Issue 11

Pages 1381–1516

    1. Cover Picture: Colloidal Synthesis of Hollow Cobalt Sulfide Nanocrystals (Adv. Funct. Mater. 11/2006)

      Y. Yin, C. K. Erdonmez, A. Cabot, S. Hughes and A. P. Alivisatos

      Version of Record online: 13 JUL 2006 | DOI: 10.1002/adfm.200690040

      Formation of cobalt sulfide hollow nanocrystals, such as those shown in the figure, via a mechanism similar to the Kirkendall Effect has been investigated in detail. Strongly temperature-dependent vacancy diffusivities result in the formation of single or multiple voids, depending on the reaction temperature. An idealized model of the diffusional process imposes two minimal requirements on material parameters for obtaining shell growth within a specific synthetic system.

    2. Inside Front Cover: Quantitative Measurement of the Local Surface Potential of π-Conjugated Nanostructures: A Kelvin Probe Force Microscopy Study (Adv. Funct. Mater. 11/2006)

      A. Liscio, V. Palermo, D. Gentilini, F. Nolde, K. Müllen and P. Samorì

      Version of Record online: 13 JUL 2006 | DOI: 10.1002/adfm.200690041

      The quantitative determination of the local surface potential of organic semiconducting nanostructures of perylene-bis-dicarboximide self-assembled at surfaces was accomplished using Kelvin probe force microscopy (KPFM). A newly devised semi-quantitative model enables simulation of the KPFM image of supramolecular adsorbates. The figure compares AFM and KPFM images of the studied self-assembled π-conjugated nanostructures.

  1. Full Papers

    1. Top of page
    2. Full Papers
    1. Colloidal Synthesis of Hollow Cobalt Sulfide Nanocrystals (pages 1389–1399)

      Y. Yin, C. K. Erdonmez, A. Cabot, S. Hughes and A. P. Alivisatos

      Version of Record online: 13 JUL 2006 | DOI: 10.1002/adfm.200600256

      Thumbnail image of graphical abstract

      Formation of cobalt sulfide hollow nanocrystals, such as those shown in the figure, via a mechanism similar to the Kirkendall Effect has been investigated in detail. Strongly temperature-dependent vacancy diffusivities result in the formation of single or multiple voids, depending on the reaction temperature. An idealized model of the diffusional process imposes two minimal requirements on material parameters for obtaining shell growth within a specific synthetic system.

    2. Polyacrylonitrile Nanofibers: Formation Mechanism and Applications as a Photoluminescent Material and Carbon-Nanofiber Precursor (pages 1400–1406)

      J. Jang, J. Bae and E. Park

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500598

      Thumbnail image of graphical abstract

      Polymer nanofibers with tunable diameters (see figure) are fabricated by microemulsion polymerization. Sphere-to-cylinder micelle transformation due to the addition of ferric chloride is crucial for nanofiber formation. The diameter of the polymer nanofibers depends on the surfactant properties, the monomer type, and the polymerization temperature. This is the first demonstration of the convenient synthesis of polymer nanofibers using a simple polymerization strategy.

    3. Quantitative Measurement of the Local Surface Potential of π-Conjugated Nanostructures: A Kelvin Probe Force Microscopy Study (pages 1407–1416)

      A. Liscio, V. Palermo, D. Gentilini, F. Nolde, K. Müllen and P. Samorì

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200600145

      Thumbnail image of graphical abstract

      The quantitative determination of the local surface potential of organic semiconducting nanostructures of perylene-bis-dicarboximide self-assembled at surfaces was accomplished using Kelvin probe force microscopy (KPFM). A newly devised semi-quantitative model enables simulation of the KPFM image of supramolecular adsorbates. The figure compares AFM and KPFM images of the studied self-assembled π-conjugated nanostructures.

    4. A New Generation of Catalytic Poly(vinylidene fluoride) Membranes: Coupling Plasma Treatment with Chemical Immobilization of Tungsten-Based Catalysts (pages 1417–1424)

      L. C. Lopez, M. G. Buonomenna, E. Fontananova, G. Iacoviello, E. Drioli, R. d'Agostino and P. Favia

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500502

      Thumbnail image of graphical abstract

      A new generation of catalytically active membranes (see figure; ca. 60 μm wide) has been developed by coupling the advantages of low-temperature plasma-modification processes with surface chemical immobilization of tungsten-based catalysts. Tungstate and decatungstate are shown to act efficiently as a catalyst for the oxidation of secondary amines and as a photocatalyst for the degradation of organic pollutants, respectively.

    5. Optically Transparent, Ultrathin Pt Films as Versatile Metal Substrates for Molecular Optoelectronics (pages 1425–1432)

      S. Conoci, S. Petralia, P. Samorì, F. M. Raymo, S. Di Bella and S. Sortino

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500893

      Thumbnail image of graphical abstract

      Ultrathin Pt films are prepared using a simple and efficient method. They exhibit a unique combination of features: excellent optical transparency, homogeneity, robustness, and conductivity, making them ideally suited to a variety of molecular optoelectronics applications (see figure). Switching of prototypical photochromic and electrochromic species is demonstrated.

    6. Generation of Self-Assembled 3D Mesostructured SnO2 Thin Films with Highly Crystalline Frameworks (pages 1433–1440)

      T. Brezesinski, A. Fischer, K.-i. Iimura, C. Sanchez, D. Grosso, M. Antonietti and B. M. Smarsly

      Version of Record online: 23 JUN 2006 | DOI: 10.1002/adfm.200600064

      Thumbnail image of graphical abstract

      Mesoporous SnO2 films with highly crystalline pore walls (see figure) have been obtained by using a novel block-copolymer template, leading to contracted spherical mesopores. The crystallization and mesostructural evolution have been investigated by various techniques, particularly by a special 2D small-angle X-ray scattering laboratory setup, without the need for a synchrotron source.

    7. Red Phosphorescent Iridium Complex Containing Carbazole-Functionalized β-Diketonate for Highly Efficient Nondoped Organic Light-Emitting Diodes (pages 1441–1448)

      Z. W. Liu, M. Guan, Z. Q. Bian, D. B. Nie, Z. L. Gong, Z. B. Li and C. H. Huang

      Version of Record online: 23 JUN 2006 | DOI: 10.1002/adfm.200600099

      Thumbnail image of graphical abstract

      Improved hole transport by introducing a carbazole-functionalized β-diketonate ligand leads to high electroluminescence efficiencies in OLEDs. The nondoped device described in this paper includes a novel red iridium complex (see figure) as the emitter. The device is compared to standard reference component devices. Improved carrier transport and a significant decrease in the triplet–triplet annihilation leads to much improved performance.

    8. Dibenzothiophene/Oxide and Quinoxaline/Pyrazine Derivatives Serving as Electron-Transport Materials (pages 1449–1456)

      T.-H. Huang, W.-T. Whang, J. Y. Shen, Y.-S. Wen, J. T. Lin, T.-H. Ke, L.-Y. Chen and C.-C. Wu

      Version of Record online: 23 JUN 2006 | DOI: 10.1002/adfm.200500823

      Thumbnail image of graphical abstract

      Dibenzothiophene/oxide and quinoxaline/pyrazine derivatives are synthesized. Time-of-flight mobility measurements reveal that the compounds have high electron mobilities (10–4–10–3 cm2 V–1 s–1). Organic light-emitting devices with promising performances are fabricated by using these compounds as the electron- transporting layer (ETL; see figure).

    9. Anisotropic Optical Properties of Semitransparent Coatings of Gold Nanocaps (pages 1457–1461)

      J. Liu, B. Cankurtaran, L. Wieczorek, M. J. Ford and M. Cortie

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500794

      Thumbnail image of graphical abstract

      Coatings of cap-shaped gold nanoparticles have been prepared on glass by polymer-templated vapor deposition. The coatings absorb and scatter near-IR radiation in a manner that depends on the polarization and inclination of the incident light. The sketch illustrates the effect of angle of inclination of the incident light on the optical extinction of a single nanocap. Applications in wavelength- and polarization-selective coatings are envisaged.

    10. Shaping Carbon Nanotubes and the Effects on Their Electrical and Mechanical Properties (pages 1462–1468)

      M. S. Wang, L.-M. Peng, J. Y. Wang and Q. Chen

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500706

      Thumbnail image of graphical abstract

      Single, freestanding carbon nanotubes (CNTs) can be shaped into morphologies with multiple bends or continuous curves by a scanning tunneling microscopy probe, and then fixed in that shape by electron-beam-induced deposition of amorphous carbon (see figure). These shaped CNTs have excellent mechanical strength and electrical conductivites that are as good as those of non-deformed CNTs.

    11. Tuning the Dimensions and Periodicities of Nanostructures Starting from the Same Polystyrene-block-poly(2-vinylpyridine) Diblock Copolymer (pages 1469–1475)

      S. Krishnamoorthy, R. Pugin, J. Brugger, H. Heinzelmann and C. Hinderling

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500524

      Thumbnail image of graphical abstract

      Arrays of micelles (see figure) with spacings that are continuously tunable over a wide range are obtained from the same block copolymer through controlled variation of the deposition conditions. Applications of the arrays as templates for replication and the synthesis of nanoparticle arrays is demonstrated.

    12. Amorphous Carbon Nanotubes with Tunable Properties via Template Wetting (pages 1476–1480)

      J.-T. Chen, K. Shin, J. M. Leiston-Belanger, M. Zhang and T. P. Russell

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500769

      Thumbnail image of graphical abstract

      Amorphous carbon nanotubes having well-defined inner and outer diameters can be prepared by solvent-casting and subsequent pyrolysis of polyacrylonitrile and polystyrene-block-polyacrylonitrile within porous anodic aluminum oxide membranes. The TEM image shows some solvent-cast nanotubes; the ribbing that is seen along the nanotube axis is due to solvent evaporation.

    13. Effect of Hole Mobility Through Emissive Layer on Temporal Stability of Blue Organic Light-Emitting Diodes (pages 1481–1487)

      S. W. Culligan, A. C.-A. Chen, J. U. Wallace, K. P. Klubek, C. W. Tang and S. H. Chen

      Version of Record online: 14 JUN 2006 | DOI: 10.1002/adfm.200500785

      Thumbnail image of graphical abstract

      Different blue-light-emitting conjugated oligomers (ADN, ANF, and ADF–see figure) have been synthesized in order to systematically study OLED instability. Measured using the transient-OLED technique, hole mobility through the emissive layer is found to play a critical role: a higher hole mobility is responsible for a longer device lifetime and a lower drive voltage at the expense of luminance yield.

    14. Nanocrystalline Metal Oxides from the Injection of Metal Oxide Sols in Coordinating Solutions: Synthesis, Characterization, Thermal Stabilization, Device Processing, and Gas-Sensing Properties (pages 1488–1498)

      M. Epifani, R. Díaz, J. Arbiol, E. Comini, N. Sergent, T. Pagnier, P. Siciliano, G. Faglia and J. R. Morante

      Version of Record online: 22 JUN 2006 | DOI: 10.1002/adfm.200500652

      Thumbnail image of graphical abstract

      Metal oxide sols are demonstrated to be suitable precursors for the low-temperature synthesis of nanocrystalline oxides by injection of the sol into a solution of tetradecene and dodecylamine,as shown in the schematic. The oxide colloids behave as spatially limited nanoreactors for the sol-to-gel transition, and the nanoparticles display outstanding gas-sensing properties even at room temperature

    15. Exploiting Chemical Switching in a Diels–Alder Polymer for Nanoscale Probe Lithography and Data Storage (pages 1499–1505)

      B. Gotsmann, U. Duerig, J. Frommer and C. J. Hawker

      Version of Record online: 23 JUN 2006 | DOI: 10.1002/adfm.200500724

      Thumbnail image of graphical abstract

      Nanoscale thermomechanical properties of reversibly crosslinked polymer films are studied. It has been shown that a reversible chemical reaction of only a few thousand molecules can be transduced into a mechanically measurable action, which opens up new perspectives in maskless nanolithography and ultrahigh-density data-storage applications (see figure).

    16. Synthesis of Amphiphilic Copolymers of Poly(ethylene oxide) and Poly(ϵ-caprolactone) with Different Architectures, and Their Role in the Preparation of Stealthy Nanoparticles (pages 1506–1514)

      J. Rieger, C. Passirani, J.-P. Benoit, K. Van Butsele, R. Jérôme and C. Jérôme

      Version of Record online: 23 JUN 2006 | DOI: 10.1002/adfm.200500110

      Thumbnail image of graphical abstract

      By comparing the effects of different macromolecular architectures of amphiphilic copolymers, based on poly(ethylene oxide) and poly(ϵ-caprolactone) segments, on the stabilization and stealthiness of polylactide nanoparticles in the bloodstream (see figure), “palm-tree” type copolymers have been found to be more efficient than diblock copolymers with similar macromolecular characteristics. These polymers may find use in preparing stealthier, more-stable nanoparticles for drug-delivery applications.

SEARCH

SEARCH BY CITATION