Advanced Functional Materials

Cover image for Vol. 21 Issue 10

May 24, 2011

Volume 21, Issue 10

Pages 1744–1946

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. Resistive Switches: Spinodal Decomposition of Blends of Semiconducting and Ferroelectric Polymers (Adv. Funct. Mater. 10/2011) (page 1744)

      Kamal Asadi, Harry J. Wondergem, Reza Saberi Moghaddam, Christopher R. McNeill, Natalie Stingelin, Beatriz Noheda, Paul W. M. Blom and Dago M. de Leeuw

      Article first published online: 16 MAY 2011 | DOI: 10.1002/adfm.201190030

      Thumbnail image of graphical abstract

      The operation of resistive switches based on phase-separated blends of organic ferroelectrics and semiconductors depends significantly on the microstructure of such systems. On page 1887, Kamal Asadi and co-workers show that the preferred bicontinuouse microstructure is formed by spinodal-decomposition phase separation of the blend. The cover image shows the corresponding microstructure probed by atomic force microscopy: the smooth valley is the featureless amorphous semiconductor phase surrounded by a crystalline ferroelectric matrix.

  2. Inside Front Cover

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. Ambipolar Transitors: Poly(diketopyrrolopyrrole-benzothiadiazole) with Ambipolarity Approaching 100% Equivalency (Adv. Funct. Mater. 10/2011) (page 1745)

      Shinuk Cho, Junghoon Lee, Minghong Tong, Jung Hwa Seo and Changduk Yang

      Article first published online: 16 MAY 2011 | DOI: 10.1002/adfm.201190031

      Thumbnail image of graphical abstract

      The image presents an ideally balanced ambipolar organic field-effect transistor (FET) in which both electrons and holes are able to move. Conventionally, conjugated polymers exhibit either high hole transport property or high electron transport property. Changduk Yang and co-workers, on page 1910, achieve ambipolar transport properties with a single-component visible-near-infrared absorbing copolymer. Its inverter, constructed with the combination of two identical ambipolar FETs, exhibits a gain much higher than values usually obtained for unipolar logics.

  3. Back Cover

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. Domains Beyond Grain Boundaries: Domains Beyond the Grain Boundary (Adv. Funct. Mater. 10/2011) (page 1746)

      Yachin Ivry, Daping Chu, James F. Scott and Colm Durkan

      Article first published online: 16 MAY 2011 | DOI: 10.1002/adfm.201190032

      Thumbnail image of graphical abstract

      Thin films of inorganic materials are used in diverse applications, typically in polycrystalline form due to their relatively simple production. On page 1827, Yachin Ivry, Colm Durkan, and co-workers discuss the use of enhanced piezoresponse force microscopy to investigate the domain distribution within neighboring grains in thin polycrystalline films of a ferroelectric-ferroelastic system. The domains are organized into areas with a correlated alignment of ferroelastic and ferroelectric domains that span multiple grain boundaries.

  4. Contents

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. Contents: (Adv. Funct. Mater. 10/2011) (pages 1747–1753)

      Article first published online: 16 MAY 2011 | DOI: 10.1002/adfm.201190033

  5. Feature Article

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. Biomaterials that Regulate Growth Factor Activity via Bioinspired Interactions (pages 1754–1768)

      Gregory A. Hudalla and William L. Murphy

      Article first published online: 29 APR 2011 | DOI: 10.1002/adfm.201002468

      Thumbnail image of graphical abstract

      In natural microenvironments, growth factor activity is regulated via noncovalent interactions with core extracellular matrix biomolecules, such as proteins and proteoglycans. These interactions have inspired the development of natural and synthetic biomaterials that can noncovalently regulate growth factor activity for tissue engineering applications. These biomaterials, and their efficacy in regenerating functional tissue, are the focus of this Feature Article.

  6. Frontispiece

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. NANOARCHITECTURES: High-Resolution Patterning of Various Large-Area, Highly Ordered Structural Motifs by Directional Photofluidization Lithography: Sub-30-nm Line, Ellipsoid, Rectangle, and Circle Arrays (Adv. Funct. Mater. 10/2011) (page 1769)

      Seungwoo Lee, Hong Suk Kang and Jung-Ki Park

      Article first published online: 16 MAY 2011 | DOI: 10.1002/adfm.201190034

      Thumbnail image of graphical abstract

      A principal challenge in nanopatterning is to beat the resolution limit of established methods. On page 1770, Seungwoo Lee, Hong Suk Kang, and Jung-Ki Park present the directional photofluidization of azopolymers, which allows the generation of large-area, highly ordered nanoarchitectures with precisely controlled structural features. Additionally, this approach can offer unprecedented flexibility in control of the final feature size, and, simultaneously, its fluidic behavior under light irradiation signifi cantly reduces the line-edge roughness

  7. Full Papers

    1. Top of page
    2. Cover Picture
    3. Inside Front Cover
    4. Back Cover
    5. Contents
    6. Feature Article
    7. Frontispiece
    8. Full Papers
    1. High-Resolution Patterning of Various Large-Area, Highly Ordered Structural Motifs by Directional Photofluidization Lithography: Sub-30-nm Line, Ellipsoid, Rectangle, and Circle Arrays (pages 1770–1778)

      Seungwoo Lee, Hong Suk Kang and Jung-Ki Park

      Article first published online: 15 MAR 2011 | DOI: 10.1002/adfm.201001927

      Thumbnail image of graphical abstract

      Directional photofluidization of azopolymers allows one to fabricate large-area nanoscale motifs with precisely controlled structural features including sizes, shapes, and orientations. Additionally, this approach can offer good control of the final feature size, and the fluidic behavior of the azopolymer under light irradiation reduces the line-edge roughness, thus improving the quality of nanostructures.

    2. Effect of Trace Solvent on the Morphology of P3HT:PCBM Bulk Heterojunction Solar Cells (pages 1779–1787)

      Lilian Chang, Hans W. A. Lademann, Jörg-Bernd Bonekamp, Klaus Meerholz and Adam J. Moulé

      Article first published online: 4 MAR 2011 | DOI: 10.1002/adfm.201002372

      Thumbnail image of graphical abstract

      The performance of bulk-heterojunction (BHJ) solar cells is strongly correlated with the nanoscale structure of the active layer. This paper highlights the role of residual solvent and solvent additives on PCBM diffusion and their effects on morphological stability. The table of contents figure shows PCBM agglomerations in P3HT/PCBM BHJ layer cast from ortho-dichlorobenzene after heat treatment. Colored “halos” around the agglomerates are PCBM-depleted regions.

    3. Synthesis of Au–CdS Core–Shell Hetero-Nanorods with Efficient Exciton–Plasmon Interactions (pages 1788–1794)

      Min Li, Xue-Feng Yu, Shan Liang, Xiao-Niu Peng, Zhong-Jian Yang, Ya-Lan Wang and Qu-Quan Wang

      Article first published online: 22 MAR 2011 | DOI: 10.1002/adfm.201002233

      Thumbnail image of graphical abstract

      Au–CdS core–shell hetero-nanorods were synthesized by using CTAB-stabilized gold nanorods as seeds and employing Ag2S as an interim layer that favored the CdS shell formation. Exciton–plasmon interactions in the Au–CdS nanorods induce shell thickness-tailored surface plasmon resonance and quench the CdS one-photon luminescence. Furthermore, these Au–CdS nanorods demonstrate an enhanced and plasmon-governed two-photon luminescence under near-infrared pulsed laser excitation.

    4. Salt Concentration Effects in Planar Light-Emitting Electrochemical Cells (pages 1795–1802)

      Stephan van Reenen, Piotr Matyba, Andrzej Dzwilewski, René A. J. Janssen, Ludvig Edman and Martijn Kemerink

      Article first published online: 22 MAR 2011 | DOI: 10.1002/adfm.201002360

      Thumbnail image of graphical abstract

      The effect of an altered ion concentration in light-emitting electrochemical cells is studied by measurement of the surface potential (graphs) and doping density (backgrounds). An increase in the ion concentration leads to an increased current density as well as the sharpening of features in the surface potential. By use of a numerical model, the underlying processes of these changes are revealed.

    5. Low-Power and High-Contrast Nanoscale All-Optical Diodes Via Nanocomposite Photonic Crystal Microcavities (pages 1803–1809)

      Xiaoyong Hu, Zhiqiang Li, Jiaxiang Zhang, Hong Yang, Qihuang Gong and Xinping Zhang

      Article first published online: 28 MAR 2011 | DOI: 10.1002/adfm.201002445

      Thumbnail image of graphical abstract

      A nanoscale integrated all-optical diode is realized via nanocomposite photnic crystal microcavities. Excellent performance is achieved by combining the strong plasmonic responses of gold nanoparticles with the all-optical tunable properties of polymeric photonic crystal microcavities. The operating power is reduced by five orders of magnitude, while the transmission contrast is enlarged by three orders of magnitude.

    6. Ultrathin SWNT Films with Tunable, Anisotropic Transport Properties (pages 1810–1815)

      Bo Li, Hyun Young Jung, Hailong Wang, Young Lae Kim, Taehoon Kim, Myung Gwan Hahm, Ahmed Busnaina, Moneesh Upmanyu and Yung Joon Jung

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002659

      Thumbnail image of graphical abstract

      Three dimensional and anisotropic, single-walled carbon nanotubes film is fabricated by template-guided fluidic assembly with complete control over the local thickness in the assembled nanostructure, realized by three-dimensional engineering of assembled substrate with alternating hydrophilic and hydrophobic microlines. The nanostructured film exhibits significant in-plane anisotropy in electrical and thermal transport properties as well as an optically transparent nature.

    7. Bulk Heterojunction Organic Photovoltaics Based on Carboxylated Polythiophenes and PCBM on Glass and Plastic Substrates (pages 1816–1826)

      Brian J. Worfolk, David A. Rider, Anastasia L. Elias, Michael Thomas, Kenneth D. Harris and Jillian M. Buriak

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201100049

      Thumbnail image of graphical abstract

      Regioregular poly[3-(carboxyalkyl)thiophene-2,5-diyl] with alkyl chains ranging from propyl to hexyl are reported and combined with PCBM, forming the photoactive layer in flexible and efficient bulk heterojunction organic photovoltaics. The molecular structure and mechanical properties of bulk heterojunctions films are characterized and deemed appropriate for roll-to-roll fabrication on flexible substrates.

    8. Domains Beyond the Grain Boundary (pages 1827–1832)

      Yachin Ivry, Daping Chu, James F. Scott and Colm Durkan

      Article first published online: 7 MAR 2011 | DOI: 10.1002/adfm.201002142

      Thumbnail image of graphical abstract

      By imaging a common piezoelectric material with nanometer resolution, we demonstrate that domains are organized into areas with a correlated alignment of the ferroelastic and ferroelectric domains, spanning multiple grain boundaries. This paves the way towards explaining long-range collective phenomena observed in such materials. We present five typical arrangements of such structures: azimuthal, radial, gradient, and short- and long- range linear domain organizations.

    9. A Printable Photopolymerizable Thermosensitive p(HPMAm-lactate)-PEG Hydrogel for Tissue Engineering (pages 1833–1842)

      Roberta Censi, Wouter Schuurman, Jos Malda, Giorgio di Dato, Petra E. Burgisser, Wouter J. A. Dhert, Cornelus F. van Nostrum, Piera di Martino, Tina Vermonden and Wim E. Hennink

      Article first published online: 5 APR 2011 | DOI: 10.1002/adfm.201002428

      Thumbnail image of graphical abstract

      3D printed constructs with varied architecture are patterned by 3D fiber deposition using a biodegradable, photopolymerizable, and thermosensitive triblock copolymer hydrogel based on PEG and poly(N-(2-hydroxypropyl)methacrylamide lactate). This biomaterial shows excellent processability and viability for embedded chondrocytes. The porous constructs can maintain separate localization of encapsulated microspheres, making this hydrogel an interesting candidate for bioprinting of hierarchically organized scaffolds.

    10. Temperature Performance of Doping-Free Top-Gate CNT Field-Effect Transistors: Potential for Low- and High-Temperature Electronics (pages 1843–1849)

      Tian Pei, Zhiyong Zhang, Zhenxing Wang, Li Ding, Sheng Wang and Lian-Mao Peng

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002563

      Thumbnail image of graphical abstract

      Operation of doping-free carbon nanotube (CNT) field-effect transistors (FET) is largely independent of the presence of dopants, thus avoiding detrimental effects due to dopant freeze-out at low temperature and dopant diffusion at high temperature, and making it possible to use doping-free CNT FETs in both low- and high-temperature electronics at a wide temperature range from 4.3 K to 573 K.

    11. A Hollow-Core, Magnetic, and Mesoporous Double-Shell Nanostructure: In Situ Decomposition/Reduction Synthesis, Bioimaging, and Drug-Delivery Properties (pages 1850–1862)

      Huixia Wu, Shengjian Zhang, Jiamin Zhang, Gang Liu, Jianlin Shi, Lingxia Zhang, Xiangzhi Cui, Meiling Ruan, Qianjun He and Wenbo Bu

      Article first published online: 8 APR 2011 | DOI: 10.1002/adfm.201002337

      Thumbnail image of graphical abstract

      A hollow core, magnetic and meso­porous double-shell nanostructure is manufactured using a novel in situ decomposition/reduction approach. The formed nanostructures are aminated by silanization for further covalent conjugation to rhodamine B isothiocyanate (RBITC) and poly(ethylene glycol) (PEG) chains, to construct a multifunctional platform for bioimaging and anticancer drug delivery.

    12. Polymeric Multilayers that Contain Silver Nanoparticles can be Stamped onto Biological Tissues to Provide Antibacterial Activity (pages 1863–1873)

      Ankit Agarwal, Kathleen M. Guthrie, Charles J. Czuprynski, Michael J. Schurr, Jonathan F. McAnulty, Christopher J. Murphy and Nicholas L. Abbott

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002662

      Thumbnail image of graphical abstract

      The design of polymeric films containing micrometer-sized beads that can be prefabricated on an elastomeric stamp and mechanically transferred onto biomedically relevant soft materials, such as silicone sheets or biological tissues, is reported. The dermis of human cadaver skin (a wound simulant) stamped with silver nanoparticle-loaded films is shown to exhibit antibacterial activity against bacteria commonly isolated from wound infections.

    13. Field-Tuneable Diamagnetism in Ferromagnetic–Superconducting Core–Shell Structures (pages 1874–1880)

      André Müller, Sara E. C. Dale, Miles A. Engbarth, Simon J. Bending, Laurence M. Peter, Andreas Knittel and Hans Fangohr

      Article first published online: 14 APR 2011 | DOI: 10.1002/adfm.201100063

      Thumbnail image of graphical abstract

      Electrodeposition is used to grow 3D mesoscopic ferromagnet–superconductor hybrid core–shell structures. Micromagnetic measurements reveal complex magnetic behavior, including re-entrant superconductivity and field-induced switching of the sign of magnetization from para(ferro-)magnetic to diamagnetic. Micromagnetic simulations performed to yield insights into the properties of our structures are in good agreement with the experimental results.

    14. A Pyridine-Containing Anthracene Derivative with High Electron and Hole Mobilities for Highly Efficient and Stable Fluorescent Organic Light-Emitting Diodes (pages 1881–1886)

      Yongduo Sun, Lian Duan, Deqiang Zhang, Juan Qiao, Guifang Dong, Liduo Wang and Yong Qiu

      Article first published online: 12 APR 2011 | DOI: 10.1002/adfm.201002691

      Thumbnail image of graphical abstract

      An efficient electron-transport material, 9,10-bis(3-(pyridin-3-yl)phenyl)anthracene (DPyPA), is presented that exhibits high electron mobility, easy injection of electrons from the cathode, and stable cationic and anionic radicals. High-performance fluorescent devices with DPyPA as the electron-transport layer have been fabricated, and achieved higher power efficiencies, lower operation voltages, and better stability than the devices with Alq3 as the electron-transport layer.

    15. Spinodal Decomposition of Blends of Semiconducting and Ferroelectric Polymers (pages 1887–1894)

      Kamal Asadi, Harry J. Wondergem, Reza Saberi Moghaddam, Christopher R. McNeill, Natalie Stingelin, Beatriz Noheda, Paul W. M. Blom and Dago M. de Leeuw

      Article first published online: 7 FEB 2011 | DOI: 10.1002/adfm.201001505

      Thumbnail image of graphical abstract

      The operation of resistive switches based on phase-separated blends of organic ferroelectrics and semiconductors depends significantly on the microstructure of such systems. The blend phase separates into amorphous rir-P3HT domains embedded in a crystalline P(VDF-TrFE) matrix with an unexpectedly mono-disperse domain-size distribution for a given rir-P3HT:P(VDF-TrFE) ratio. A simple model is used to interpret the out of plane current through the film as a function of blend composition.

    16. Carbon Nanotube Alignment via Electrohydrodynamic Patterning of Nanocomposites (pages 1895–1901)

      Pola Goldberg-Oppenheimer, Dominik Eder and Ullrich Steiner

      Article first published online: 25 MAR 2011 | DOI: 10.1002/adfm.201002692

      Thumbnail image of graphical abstract

      The patterning of a carbon nanotube(CNT)-polymer composite in an electric field gives rise to a pillar pattern. The pillar formation results in the orientation of the CNTs along the cylinder axis. Above the CNT percolation threshold, a considerable increase in conductivity of the nanocomposite is obtained. This method provides a route for patterning CNTs into tailor-made structures inside matrix materials, which is appealing for the potential integration of nanocomposites into functional devices.

    17. Yolk-like Micro/Nanoparticles with Superparamagnetic Iron Oxide Cores and Hierarchical Nickel Silicate Shells (pages 1902–1909)

      Qunling Fang, Shouhu Xuan, Wanquan Jiang and Xinglong Gong

      Article first published online: 28 MAR 2011 | DOI: 10.1002/adfm.201002191

      Thumbnail image of graphical abstract

      Yolk-like microparticleswith superparamagnetic iron oxide (SPIO) cores and hierarchical nickel silicate (NS) shells, designated yolk SPIO@NS, are fabricated by combining the versatile sol–gel process and hydrothermal reaction. Various yolk/shell structures with tunable shell thicknesses and core sizes are successfully prepared by controlling the experimental parameters.

    18. Poly(diketopyrrolopyrrole-benzothiadiazole) with Ambipolarity Approaching 100% Equivalency (pages 1910–1916)

      Shinuk Cho, Junghoon Lee, Minghong Tong, Jung Hwa Seo and Changduk Yang

      Article first published online: 25 MAR 2011 | DOI: 10.1002/adfm.201002651

      Thumbnail image of graphical abstract

      An equivalent ambipolar organic field-effect transistor (FET) is achieved by using a single-component visible–near infrared absorbing diketopyrrolopyrrole (DPP)–benzothiadiazole (BTZ) copolymer (PDTDPP-alt-BTZ), revealing ideally balanced charge carrier mobilities for both electrons (μe = 0.09 cm2 V−1 s−1) and holes (μh = 0.1 cm2 V−1 s−1).

    19. Electronic Conductivity and Defect Chemistry of Heterosite FePO4 (pages 1917–1921)

      Changbao Zhu, Katja Weichert and Joachim Maier

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002059

      Thumbnail image of graphical abstract

      Heterosite FePO4 exhibits a predominant electronic conductivity (σeon) which is of n-type. The main electronic and ionic defects are electrons and Li-interstitials ([Lii•] = [e′]) as suggested by conductivity investigations of solid solutions LixFePO4 (x ≤ 0.02) as well as the pO2 dependence of σeon. With reference to the ionic and electronic ground structure of heterosite, these defects are in fact expected.

    20. Well-Ordered Large-Pore Mesoporous Anatase TiO2 with Remarkably High Thermal Stability and Improved Crystallinity: Preparation, Characterization, and Photocatalytic Performance (pages 1922–1930)

      Wei Zhou, Fanfei Sun, Kai Pan, Guohui Tian, Baojiang Jiang, Zhiyu Ren, Chungui Tian and Honggang Fu

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002535

      Thumbnail image of graphical abstract

      Well-ordered, large-pore mesoporous anatase TiO2 with high thermal stability and improved crystallinity was fabricated by an evaporation-induced self-assembly approach, using encircling ethylenediamine protectors to maintain the liquid crystal mesophase structure, followed by high temperature calcination. The TiO2 exhibited enhanced photocatalytic activity due to the integrated large-pore mesoporous structure, large surface area, and high crystallinity.

    21. Profiles of Work Function Shifts and Collective Charge Transfer in Submonolayer Metal–Organic Films (pages 1931–1940)

      Benjamin J. Topham, Manoranjan Kumar and Zoltán G. Soos

      Article first published online: 4 APR 2011 | DOI: 10.1002/adfm.201002677

      Thumbnail image of graphical abstract

      Work function profiles Δ(θ) of submono­layer metal–organic films are nonlinear in the monolayer coverage θ = d/dML ≤ 1. Nonlinear profiles indicate collective behavior of surface dipoles that is modeled as charge transfer (CT) at the interface and dipole–dipole repulsion. The phenomenological model accounts for published Δ(θ) profiles in terms of decreasing CT with increasing θ.

    22. Multistage Coloring Electrochromic Device Based on TiO2 Nanotube Arrays Modified with WO3 Nanoparticles (pages 1941–1946)

      Yan-Yan Song, Zhi-Da Gao, Jian-Hua Wang, Xing-Hua Xia and Robert Lynch

      Article first published online: 22 MAR 2011 | DOI: 10.1002/adfm.201002258

      Thumbnail image of graphical abstract

      WO3 nanoparticles loaded in TiO2 nanotube arrarys are fabricated by chemical bath deposition in combination with a pyrolysis process. The 3-dimensional WO3/TiO2 junction in the nanotube arrays results in a multistage coloring electrochromic response and enhanced electrochromic properties.

SEARCH

SEARCH BY CITATION