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991.
Synthesis of Alternating Donor–Acceptor Ladder‐Type Molecules and Investigation of Their Multiple Charge‐Transfer Pathways 下载免费PDF全文
Mohammad A. Awais Dr. Alexander S. Filatov Prof. Luping Yu 《Angewandte Chemie (International ed. in English)》2018,57(22):6442-6448
We describe the synthesis as well as the optical and charge‐transport properties of a series of donor–acceptor (D‐A) ladder‐type heteroacenes. These molecules are stable, soluble, and contain up to 24 fused rings. Structural analyses indicated that the backbones of S 10r and Se 10r are bent in single crystals. The three 10‐ring heteroacenes were functionalized with thiol anchoring groups and used for single‐molecular conductance measurements. The highest conductance was observed for molecular wires containing a benzoselenadiazole (BSD) moiety, which exhibits the narrowest band gap. Multiple charge‐transport pathways were observed in molecular wires containing either benzothiadiazole (BTD) or BSD. The conductance is a complex function of both energy gap and orbital alignment. 相似文献
992.
Alan G. MacDiarmid 《Angewandte Chemie (International ed. in English)》2001,40(14):2581-2590
Since the initial discovery in 1977, that polyacetylene (CH)x, now commonly known as the prototype conducting polymer, could be p‐ or n‐doped either chemically or electrochemically to the metallic state, the development of the field of conducting polymers has continued to accelerate at an unexpectedly rapid rate and a variety of other conducting polymers and their derivatives have been discovered. Other types of doping are also possible, such as “photo‐doping” and “charge‐injection doping” in which no counter dopant ion is involved. One exciting challenge is the development of low‐cost disposable plastic/paper electronic devices. Conventional inorganic conductors, such as metals, and semiconductors, such as silicon, commonly require multiple etching and lithographic steps in fabricating them for use in electronic devices. The number of processing and etching steps involved limits the minimum price. On the other hand, conducting polymers combine many advantages of plastics, for example, flexibility and processing from solution, with the additional advantage of conductivity in the metallic or semiconducting regimes; however, the lack of simple methods to obtain inexpensive conductive polymer shapes/patterns limit many applications. Herein is described a novel, simple, and cheap method to prepare patterns of conducting polymers by a process which we term, “Line Patterning”. 相似文献
993.
A new kind of stable aqueous conductive ink with silver nanoflakes was developed, which was also used to fabricate conductive patterns on weighing paper for flexible electronics by direct writing. Silver nanoflakes of different sizes were characterized by transmission electron microscopy. The physical properties of the conductive ink were investigated by a dynamic contact angle system, Ubbelohde viscometer, and a surface tension instrument. Conductive properties of paper‐based conductive patterns were also investigated by 4‐point probe, scanning electron microscopy, X‐ray diffraction and Uscan explorer with a 3D profilometer system. It is demonstrated how the formulation of conductive ink affects the surface morphology, microstructure conductivity, and line width of conductive patterns. It can be obtained that the paper‐based conductive patterns have low resistivity. Especially, when the sintering condition is 200 °C for 20 min, the resistivity can be down to 9.4 μΩ?cm. The application of the ink on an antenna for radio frequency identification was also studied. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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996.
Manuel Piacenza Dr. Davide Comoretto Dr. Martin Burger Dr. Valentina Morandi Dr. Franco Marabelli Prof. Dr. Carmella Martinelli Dr. Gianluca M. Farinola Prof. Dr. Antonio Cardone Dr. Giuseppe Gigli Prof. Dr. Fabio Della Sala Dr. 《Chemphyschem》2009,10(8):1284-1290
Ring the changes : Experimental Raman spectra of fluorinated and non‐fluorinated polyphenylenevinylenes are assigned according to quantum chemical calculations for oligomer model systems (see picture). Characteristic differences in the spectra can be traced back to strong inter‐ring distortion of the fluorinated compounds.
997.
Dr. Eun Cheol Lee Dr. Young Cheol Choi Dr. Woo Youn Kim Dr. N. Jiten Singh Dr. Sik Lee Prof. Ji Hoon Shim Prof. Kwang S. Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(40):12141-12146
Given that half‐metals are promising futuristic materials for spintronics, organic materials showing half‐metal character are highly desirable for spintronic devices, not only owing to their weak spin‐orbit and hyperfine interactions, but also their light and flexible properties. We predict that a two‐dimensional organic 2,4,6‐tri‐(1,3,5‐triazinyl)methyl radical polymer has half‐metallic properties as well as a spontaneous magnetic ordering at ambient temperature. The quantum transmission is studied based on the nonequilibrium Green function theory coupled with density functional theory. The half‐metallic property in the triazine‐based polymer depends mainly on the nature of the p‐band in contrast to of conventional half metals in which the nature of the d‐band is more important. 相似文献
998.
透明导电薄膜是一种在可见光范围内透光率较高、导电性优良的薄膜材料.近年来随着智能手机、平板电脑等电子产品日益普及,透明导电薄膜受到越来越多的关注.本文分析了目前占据市场统治地位的掺锡氧化铟透明导电薄膜的缺点以及近年来国内外对透明导电薄膜开展的研究工作,总结了目前在印刷电子领域透明导电薄膜的主要研究方向,一方面是在传统金属氧化物薄膜基础上的改进;另一方面是寻找新型透明导电薄膜材料,并分别综述了各个研究方向的最新进展. 相似文献
999.
A Solution‐Processable Donor–Acceptor Compound Containing Boron(III) Centers for Small‐Molecule‐Based High‐Performance Ternary Electronic Memory Devices 下载免费PDF全文
Dr. Chun‐Ting Poon Dr. Di Wu Dr. Wai Han Lam Prof. Dr. Vivian Wing‐Wah Yam 《Angewandte Chemie (International ed. in English)》2015,54(36):10569-10573
A novel small‐molecule boron(III)‐containing donor–acceptor compound has been synthesized and employed in the fabrication of solution‐processable electronic resistive memory devices. High ternary memory performances with low turn‐on (VTh1=2.0 V) and distinct threshold voltages (VTh2=3.3 V), small reading bias (1.0 V), and long retention time (>104 seconds) with a large ON/OFF ratio of each state (current ratio of “OFF”, “ON1”, and “ON2”=1:103:106) have been demonstrated, suggestive of its potential application in high‐density data storage. The present design strategy provides new insight in the future design of memory devices with multi‐level transition states. 相似文献
1000.
Sambasiva R. Bheemireddy Dr. Pamela C. Ubaldo Peter W. Rose Dr. Aaron D. Finke Prof. Junpeng Zhuang Prof. Lichang Wang Prof. Kyle N. Plunkett 《Angewandte Chemie (International ed. in English)》2015,54(52):15762-15766
A new class of stabilized pentacene derivatives with externally fused five‐membered rings are prepared by means of a key palladium‐catalyzed cyclopentannulation step. The target compounds are synthesized by chemical manipulation of a partially saturated 6,13‐dibromopentacene precursor that can be fully aromatized in a final step through a DDQ‐mediated dehydrogenation reaction (DDQ=2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone). The new 1,2,8,9‐tetraaryldicyclopenta[fg,qr]pentacene derivatives have narrow energy gaps of circa 1.2 eV and behave as strong electron acceptors with lowest unoccupied molecular orbital energies between ?3.81 and ?3.90 eV. Photodegradation studies reveal the new compounds are more photostable than 6,13‐bis(triisopropylsilylethynyl)pentacene (TIPS‐pentacene). 相似文献