Home About us Contact
|
Home About us Contact | ||
|
|
||
Organic Single Crystals (organic + single_crystal)
Selected AbstractsBerichtigung: Strong Two-Photon Excited Fluorescence and Stimulated Emission from an Organic Single Crystal of an Oligo(Phenylene Vinylene)ANGEWANDTE CHEMIE, Issue 36 2010Fei Gao No abstract is available for this article. [source] Strong Two-Photon Excited Fluorescence and Stimulated Emission from an Organic Single Crystal of an Oligo(Phenylene Vinylene),ANGEWANDTE CHEMIE, Issue 4 2010Fei Gao Niedrig rein, hoch raus: Einkristalle eines Thiomethyl-terminierten Oligo(phenylenvinylens) zeigen einzigartige photonische Eigenschaften , einschließlich einer starken anisotropen Fluoreszenz (siehe optische und Fluoreszenzaufnahmen; Pfeil: Polarisationsrichtung), hoher Quantenausbeuten, großer Zweiphotonenabsorptionsquerschnitte und einer stimulierten Emission ,, die sie zu Kandidaten für optoelektronische Anwendungen wie Hochkonversionslaser machen. [source] Organic Single Crystals: Azeotropic Binary Solvent Mixtures for Preparation of Organic Single Crystals (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 22 2009Mater. The inside cover of this issue illustrates the solution-phase self-assembly of organic single crystals by using azeotropic binary solvent mixtures, described by X. Li et al. on page 3610, and is a snap-shot taken during the self-assembly of tri-isopropylsilylethynyl pentacene single crystals from an azeotropic binary solvent mixture of isopropanol plus toluene, on a silicon substrate. These needle-like crystals were growing with time while floating in the bulk of the solution during solvent evaporation, with bright colors showing their birefringence. [source] Azeotropic Binary Solvent Mixtures for Preparation of Organic Single CrystalsADVANCED FUNCTIONAL MATERIALS, Issue 22 2009Xiaoran Li Abstract Here, a new approach is introduced to prepare large single crystals of ,-conjugated organic molecules from solution. Utilizing the concept of azeotropism, single crystals of tri-isopropylsilylethynyl pentacene (TIPS-PEN) with dimensions up to millimeters are facilely self-assembled from homogeneous solutions comprising two solvents with opposing polarities and a positive azeotropic point. At solvent compositions close to the azeotropic point, an abrupt transition of morphology from polycrystalline thin-films to large single crystals is found. How to adjust the initial ratio of the binary solvents so that the change in solvent composition during evaporation favors the specific H-aggregation and promotes an efficient self-assembly of TIPS-PEN is explained. The charge-carrier (hole) mobilities are substantially enhanced by a factor of 4 from the morphology of thin-films to large single crystals used as active layer in field-effect transistors. Additionally, this approach is extended to other ,,, stacked organic molecules to elucidate its broad applicability. [source] Micrometer-Sized Organic Single Crystals, Anisotropic Transport, and Field-Effect Transistors of a Fused-Ring ThienoaceneADVANCED MATERIALS, Issue 44 2009Rongjin Li Hexagonal micrometer-sized organic single crystals of a fused-ring thienoacene are grown controllably by physical vapor transport over a large area. A "two-dimensional organic-ribbon mask" technique is developed to fabricate organic field-effect transistors based on an individual microcrystal. The accomplished transistors exhibit mobility as high as 1.8,cm2V,1s,1 with on/off ratios of typically >107. [source] Organic Electronics: Solution-Grown, Macroscopic Organic Single Crystals Exhibiting Three-Dimensional Anisotropic Charge-Transport Properties (Adv. Mater.ADVANCED MATERIALS, Issue 18 200918/2009) Organic single crystals have the potential to delivering novel electronic devices based on three-dimensional anisotropic electronic transport. The cover shows single crystals of 4-hydroxycyanobenzene (4HCB) grown from solution behind a distorted-perspective partial representation of the crystalline structure hinting at their molecular constituents. The carrier mobility, anisotropic along the three crystallographic axes, is discussed by Fraleoni-Morgera, Fraboni, Femoni, and co-workers on p. 1835. Dr. George Kourousias is acknowledged for the cover design and artwork. [source] Organic Single Crystals: Azeotropic Binary Solvent Mixtures for Preparation of Organic Single Crystals (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 22 2009Mater. The inside cover of this issue illustrates the solution-phase self-assembly of organic single crystals by using azeotropic binary solvent mixtures, described by X. Li et al. on page 3610, and is a snap-shot taken during the self-assembly of tri-isopropylsilylethynyl pentacene single crystals from an azeotropic binary solvent mixture of isopropanol plus toluene, on a silicon substrate. These needle-like crystals were growing with time while floating in the bulk of the solution during solvent evaporation, with bright colors showing their birefringence. [source] Probing the Anisotropic Field-Effect Mobility of Solution-Deposited Dicyclohexyl-,-quaterthiophene Single Crystals,ADVANCED FUNCTIONAL MATERIALS, Issue 10 2007Abstract Measuring the anisotropy of the field-effect mobility provides insight into the correlation between molecular packing and charge transport in organic semiconductor materials. Single-crystal field-effect transistors are ideal tools to study intrinsic charge transport because of their high crystalline order and chemical purity. The anisotropy of the field effect mobility in organic single crystals has previously been studied by lamination of macroscopically large single crystals onto device substrates. Here, a technique is presented that allows probing of the mobility anisotropy even though only small crystals are available. Crystals of a soluble oligothiophene derivative are grown in bromobenzene and drop-cast onto substrates containing arrays of bottom-contact gold electrodes. Mobility anisotropy curves are recorded by measuring numerous single crystal transistor devices. Surprisingly, two mobility maxima occur at azimuths corresponding to both axes of the rectangular cyclohexyl-substituted quaterthiophene (CH4T) in-plane unit cell, in contrast to the expected tensorial behavior of the field effect mobility. [source] Micrometer-Sized Organic Single Crystals, Anisotropic Transport, and Field-Effect Transistors of a Fused-Ring ThienoaceneADVANCED MATERIALS, Issue 44 2009Rongjin Li Hexagonal micrometer-sized organic single crystals of a fused-ring thienoacene are grown controllably by physical vapor transport over a large area. A "two-dimensional organic-ribbon mask" technique is developed to fabricate organic field-effect transistors based on an individual microcrystal. The accomplished transistors exhibit mobility as high as 1.8,cm2V,1s,1 with on/off ratios of typically >107. [source] Organic Single-Crystal Schottky Gate TransistorsADVANCED MATERIALS, Issue 36 2009Toshihiko Kaji Schottky contacts and Schottky gate transistors on organic single crystals are successfully fabricated, and enable the complete understanding of the operating mechanism as well as a full description of the energy-band diagram. This represents a considerable step forward in the understanding of organic semiconductors, and offers a viable route for organic-device design. [source] Controlled Deposition of Crystalline Organic Semiconductors for Field-Effect-Transistor ApplicationsADVANCED MATERIALS, Issue 12 2009Shuhong Liu Abstract The search for low-cost, large-area, flexible devices has led to a remarkable increase in the research and development of organic semiconductors, which serve as one of the most important components for organic field-effect transistors (OFETs). In the current review, we highlight deposition techniques that offer precise control over the location or in-plane orientation of organic semiconductors. We focus on various vapor- and solution-processing techniques for patterning organic single crystals in desired locations. Furthermore, the alignment of organic semiconductors via different methods relying on mechanical forces, alignment layers, epitaxial growth, and external magnetic and electric fields are surveyed. The advantages, limitations, and applications of these techniques in OFETs are also discussed. [source] | ||||||||||