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High-Yield Synthesis (high-yield + synthesis)
Selected AbstractsHigh-Yield Synthesis and Electrochemical and Photovoltaic Properties of Indene-C70 BisadductADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Youjun He Abstract [6, 6]-Phenyl-C61 -butyric acid methyl ester (PC60BM) is the widely used acceptor material in polymer solar cells (PSCs). Nevertheless, the low LUMO energy level and weak absorption in visible region are its two weak points. For enhancing the solar light harvest, the soluble C70 derivative PC70BM has been used as acceptor instead of PC60BM in high efficiency PSCs in recent years. But, the LUMO level of PC70BM is the same as that of PC60BM, which is too low for the PSCs based on the polymer donors with higher HOMO level, such as poly (3-hexylthiophene) (P3HT). Here, a new soluble C70 derivative, indene-C70 bisadduct (IC70BA), is synthesized with high yield of 58% by a one-pot reaction of indene and C70 at 180 °C for 72 h. The electrochemical properties and electronic energy levels of the fullerene derivatives are measured by cyclic voltammetry. The LUMO energy level of IC70BA is 0.19 eV higher than that of PC70BM. The PSC based on P3HT with IC70BA as acceptor shows a higher Voc of 0.84 V and higher power conversion efficiency (PCE) of 5.64%, while the PSC based on P3HT/PC60BM and P3HT/PC70BM displays Voc of 0.59 V and 0.58 V, and PCE of 3.55% and 3.96%, respectively, under the illumination of AM1.5G, 100 mW cm,2. The results indicate that IC70BA is an excellent acceptor for the P3HT-based PSCs and could be a promising new acceptor instead of PC70BM for the high performance PSCs based on narrow bandgap conjugated polymer donor. [source] High-Yield Synthesis of Ultrathin Metal Nanowires in Carbon Nanotubes,ANGEWANDTE CHEMIE, Issue 44 2009R. Kitaura Prof. Mit Schutzhülle stabil: Metallnanodrähte mit Durchmessern von nur ca. 1.7,nm wurden in hohen Ausbeuten im Inneren von Kohlenstoff-Nanoröhren (CNTs) synthetisiert. Dank der Ummantelung durch die CNT-Wand sind die Nanodrähte aus einzelnen Atomen selbst bei Umgebungsbedingungen vor Oxidation und Zerfall der Struktur geschützt. [source] Cyclization of 1-(2-Alkynylphenyl)-3,3-dialkyltriazenes: A Convenient, High-Yield Synthesis of Substituted Cinnolines and Isoindazoles.CHEMINFORM, Issue 6 2003David B. Kimball Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: High-Yield Synthesis of Novel Imidazoles and Triazoles from Alcohols and Phenols.CHEMINFORM, Issue 17 2001Vincent C. O. Njar Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Facile High-Yield Synthesis of Polyaniline Nanosticks with Intrinsic Stability and Electrical ConductivityCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2008Xin-Gui Li Prof. Abstract Chemical oxidative polymerization at 15,°C was used for the simple and productive synthesis of polyaniline (PAN) nanosticks. The effect of polymerization media on the yield, size, stability, and electrical conductivity of the PAN nanosticks was studied by changing the concentration and nature of the acid medium and oxidant and by introducing organic solvent. Molecular and supramolecular structure, size, and size distribution of the PAN nanosticks were characterized by UV/Vis and IR spectroscopy, X-ray diffraction, laser particle-size analysis, and transmission electron microscopy. Introduction of organic solvent is advantageous for enhancing the yield of PAN nanosticks but disadvantageous for formation of PAN nanosticks with small size and high conductivity. The concentration and nature of the acid medium have a major influence on the polymerization yield and conductivity of the nanosized PAN. The average diameter and length of PAN nanosticks produced with 2,M HNO3 and 0.5,M H2SO4 as acid media are about 40 and 300,nm, respectively. The PAN nanosticks obtained in an optimal medium (i.e., 2,M HNO3) exhibit the highest conductivity of 2.23,S,cm,1 and the highest yield of 80.7,%. A mechanism of formation of nanosticks instead of nanoparticles is proposed. Nanocomposite films of the PAN nanosticks with poly(vinyl alcohol) show a low percolation threshold of 0.2,wt,%, at which the film retains almost the same transparency and strength as pure poly(vinyl alcohol) but 262,000 times the conductivity of pure poly(vinyl alcohol) film. The present synthesis of PAN nanosticks requires no external stabilizer and provides a facile and direct route for fabrication of PAN nanosticks with high yield, controllable size, intrinsic self-stability, strong redispersibility, high purity, and optimizable conductivity. [source] High-yield synthesis of milligram amounts of isotopically enriched methylmercury (CH3198HgCl)APPLIED ORGANOMETALLIC CHEMISTRY, Issue 2 2004Chrystelle Bancon-Montigny Isotopically enriched CH3198HgCl (MeHgCl) has been synthesized from commercially available elemental 198Hg (96% isotopic purity). Elemental mercury is first converted to HgCl2 and subsequently reacted with methylcobalamin to produce MeHgCl. The resulting MeHgCl is isolated from the reaction mixture by successive extractions with toluene and dried over Na2SO4. The product structure was verified using gas chromatography,mass spectrometry (GC,MS) and the isotopic composition was determined by GC,inductively coupled plasma MS. The yield obtained is 99%. The proposed method allows preparation of milligram quantities of MeHgCl in one step, minimizing the cost of this synthesis. Copyright © 2004 John Wiley & Sons, Ltd. [source] [Pt(topy)(Htopy)(ONO2)] complex (Htopy = 2- p -tolylpyridine) and its analogs: 195Pt NMR spectra and fabrication of light-emitting devicesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2009Hiroto Fukuda Abstract We report fast, high-yield syntheses of a series of [Pt(C,N)(HC,N)X] complexes, where HC,N is 2-phenylpyridine (Hppy) or 2- p -tolylpyridine (Htopy) and X, is Cl,, Br,, I,, ONO2,, NO2, or SCN,. The structure of [Pt(topy)(Htopy)(ONO2)] was analyzed by single-crystal X-ray diffraction. Substitution of Cl, with Br, or I, in our complexes shifted the 195Pt NMR peaks upfield in the order Cl, < Br, < I,, but the magnitudes of their shifts were one-tenth those observed for non-cyclometalated platinum(II) complexes. As the two nitrato complexes showed strong emissions in acetonitrile solution,three to six times those of other complexes,they were used to fabricate OLEDs. Although their emissions were not particularly strong, devices fabricated with platinum(II) complexes containing bulky ligands emitted green light with a short lifetime (,). Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||