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1.
The advancement of organic electronics has been continually pushed by the need for stable and high performance acceptor materials. By utilizing inexpensive and stable indigo dye as a starting material, Bay‐Annulated Indigo (BAI) provides a new motif for the development of semiconducting materials. Modular and straightforward synthesis makes BAI an outstanding platform for molecular design, while excellent stability, strong absorption, and high ambipolar mobility render BAI‐based materials excellent candidates for organic electronics. BAI‐based polymers and small molecules have taken advantage of these properties to show promising results in a variety of applications. 相似文献
2.
Michael Meier Dr. Lei Ji Dr. Jörn Nitsch Dr. Ivo Krummenacher Andrea Deißenberger Dr. Dominic Auerhammer Dr. Marius Schäfer Prof. Dr. Todd B. Marder Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(18):4707-4712
A novel thiophene-bridged donor–acceptor system was synthesized with a carbazole as donor and a borole as acceptor unit. The borole group was successfully installed via the tin–boron exchange reaction of 1,1-dimethyl-2,3,4,5-tetraphenylstannole with 9-(5-(dibromoboryl)thiophen-2-yl)carbazole. The effect of the borole on the optoelectronic properties of the donor–acceptor system was explored by spectroscopic (UV/Vis and fluorescence spectroscopy), electrochemical (cyclic voltammetry) and theoretical (TD-DFT) methods as well as by modifying its structure. The corresponding donor–acceptor compound bearing the widely employed dimesitylboryl acceptor group was also synthesized for comparison. 相似文献
3.
Anxun Zheng Chang Shen Prof. Qian Tang Dr. Cheng-Bin Gong Dr. Cheuk-Fai Chow 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(41):9643-9649
Herein, a catalytic chemosensing assay (CCA), based on a bimetallic complex, [RuII(bpy)2(CN)2]2(CuII)2 (bpy=2,2′-bipyridine), is described. This complex integrates a task-specific catalyst (CuI-catalyst) and a signaling unit ([RuII(bpy)2(CN)2]) to specifically hydrolyze methyl parathion, a highly toxic organophosphate (OP) pesticide. The bimetallic complex catalyzed the hydrolysis of the phosphate ester to generate o,o-dimethyl thiophosphate (DTP) anion and 4-nitrophenolate. Intrinsically, 4-nitrophenolate absorbed UV/Vis light at λmax=400 nm, creating the first level of the chemosensing signal. DTP interacted with the original complex to displace the chromophore, [RuII(bpy)2(CN)2], which was monitored by spectrofluorometry; this was classified as the second level of chemosensing signal. By integrating both spectroscopic and spectrofluorometric signals with a simple AND logic gate, only methyl parathion was able to provide a positive response. Other aromatic and aliphatic OP pesticides (diazinon, fenthion, meviphos, terbufos, and phosalone) and 4-nitrophenyl acetate provided negative responses. Furthermore, owing to the metal-catalyzed hydrolysis of methyl parathion, the CCA system led to the detoxification of the pesticide. The CCA system also demonstrated its catalytic chemosensing properties in the detection of methyl parathion in real samples, including tap water, river water, and underground water. 相似文献
4.
利用ANSYS 对低活化铁素体马氏体(RAFM)钢进行非熔化极气体保护焊(TIG 焊)与电子束焊的抗疲劳模拟分析,再利用SDS200 电液伺服疲劳试验机对TIG 焊和电子束焊的两种RAFM 钢试件进行实验。通过施加相同梯度负荷对TIG 焊和电子束焊试件进行焊缝的疲劳性能实验。与实验结果对比分析,结果显示电子束焊优于 TIG 焊,但在一定负载下可以用TIG 焊代替电子束焊。 相似文献
5.
Junko Hirota Dr. Kazuteru Usui Dr. Yasufumi Fuchi Masaomi Sakuma Shota Matsumoto Ryusuke Hagihara Prof. Dr. Satoru Karasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(65):14943-14952
Water-soluble donor–acceptor-type fluorophore 15Nap-Cl having two trifluoromethyl groups and a Cl group on a 1,5-aminonaphthyridine framework was prepared. Fluorophore 15Nap-Cl showed strong solvatochromic fluorescence, and, as the solvent polarity increased, a bathochromic shift was observed accompanied by an increase in the fluorescence quantum yield. In addition, in the presence of amines such as ethylamine, diethylamine, and aniline, further considerable bathochromic shifts in the fluorescence were observed. Density functional calculations identified the source of the fluorescence behavior as exciplex formation between 15-Nap-Cl and the corresponding amine. The fluorescence behavior was exploited to fabricate a sensor that can identify various primary, secondary, and tertiary amines. 相似文献
6.
David Tong Jackie Wu Nathan Bazinski Donghyun Koo Naresh Vemula Prof. Dr. Brian L. Pagenkopf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(67):15244-15247
Cycloadditions of strained carbocycles promoted by Lewis acids are powerful methods to construct heterocyclic frameworks. In fact, the formal [3+2] cycloadditions of donor–acceptor (DA) cyclopropanes with nitriles has seen particular success in synthesis. In this work, we report on the first [4+2] cycloaddition of nitriles with DA cyclobutanes by Lewis acid activation. Tetrahydropyridine derivatives were obtained in up to 91 % yield from various aryl-activated cyclobutane diesters and aliphatic or aromatic nitriles. 相似文献
7.
Hydrodynamic cavitation (HC) and Fe(II) are advanced oxidation processes, in which pentachlorophenol (PCP) is treated by the redox method of activating persulfate (PS). The kinetics and mechanism of the HC and Fe(II) activation of PS were examined in aqueous solution using an electron spin resonance (ESR) spin trapping technique and radical trapping with pure compounds. The optimum ratio of Fe(II)/PS was 1:2, and the hydroxyl radical (HO) and sulfate radical (SO4−) generation rate were 5.56 mM h−1 and 8.62 μM h−1, respectively. The generation rate and Rct of HO and SO4− at pH 3 and 50 °C in the Fe(II)/PS/HC system are 7584.6 μM h−1, 0.013 and 24.02 μM h−1, 3.95, respectively. The number of radicals was reduced as the pH increased, and it increased with increasing temperature. The PCP reaction rate constants was 4.39 × 10−2 min−1 at pH 3 and 50 °C. The activation energy was 10.68 kJ mol−1. In addition, the mechanism of PCP treatment in the Fe(II)/PS/HC system was a redox reaction, and the HO−/SO4− contribution was 81.1 and 18.9%, respectively. In this study, we first examined PCP oxidation through HO and SO4− quantification using only the Fe(II)/PS/HC process. Furthermore, the results provide the foundation for activation of PS by HC and Fe(II), but also provide a data basis for similar organic treatments other than PCP. 相似文献
8.
《Current Applied Physics》2020,20(1):172-177
Doping is a widely-implemented strategy for enhancing the inherent electrical properties of metal oxide charge transport layers in photovoltaic devices because higher conductivity of electron transport layer (ETL) can increment the photocurrent by reducing the series resistance. To improve the conductivity of ETL, in this study we doped the ZnO layer with aluminum (Al), then investigated the influence of AZO on the performance of inverted bulk heterojunction (BHJ) polymer solar cells based on poly [[4,8-bis [(2-ethylhexyl)oxy]benzo [1,2-b:4,5-b’]dithiophene-2,6-diyl]-[3-fluoro-2[(2-ethylhexyl)-carbonyl]-thieno-[3,4-b]thiophenediyl ]] (PTB7):[6,6]-phenyl C71 butyric acid methyl ester (PC71BM). The measured conductivity of AZO was ~10−3 S/cm, which was two orders of magnitude higher than that of intrinsic ZnO (~10−5 S/cm). By decreasing the series resistance (Rs) in a device with an AZO layer, the short circuit current (Jsc) increased significantly from 15.663 mA/cm2 to 17.040 mA/cm2. As a result, the device with AZO exhibited an enhanced power conversion efficiency (PCE) of 8.984%. 相似文献
9.
Electron transfer reactions are the most important processes at electrochemical interfaces. They are determined by the interplay between the interaction of the reactant with the solvent and the electronic levels of the electrode surface. Theoretical treatments only based on Density Functional Theory calculations are not sufficient. This review emphasizes mainly the effect of the electronic structure of the electrode material on electron transfer under different kinetic regimes. Our goal is to understand experimental results in the framework of a theory valid for arbitrary strengths of electronic coupling. 相似文献
10.
Rational design of methacrylate monomers containing oxadiazole moieties for single‐layer organic light emitting devices 下载免费PDF全文
Bogdan Zdyrko Yuriy Bandera Volodymyr Tsyalkovsky Christopher F. Huebner Jamie A. Shetzline Parul Rungta Ryan D. Roeder Charles Tonkin Stephen E. Creager Stephen H. Foulger 《Journal of Polymer Science.Polymer Physics》2015,53(23):1663-1673
Methacrylate derived monomers functionalized with pendant oxadiazole moieties were synthesized and copolymerized with carbazole containing monomers to form polymers with electron and hole transporting fragments in the same molecule. Substituents on the oxidazole moiety were varied with the purpose of bandgap tuning and performance optimization when employed in single‐layer organic light emitting devices (OLED). Quantum mechanical calculations of the HOMO‐LUMO levels of the oxidazole derivatives were used to down‐select promising candidates for chemical synthesis and testing in single‐layer OLEDs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1663–1673 相似文献