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991.
Cheng Wei Sheng Ren Wang Yan Liu Yuting Tong Bihai Chen Ping Wang Song 《Transition Metal Chemistry》2021,46(1):81-89
Transition Metal Chemistry - Four iridium(III) complexes (1–4) with sulfur-containing phenylpyridazine ligands were successfully synthesized and characterized. The structure of complex 3 was... 相似文献
992.
Simon Muench René Burges Alexandra Lex-Balducci Johannes C. Brendel Michael Jäger Christian Friebe Andreas Wild Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2021,59(6):494-501
Despite intensive scientific efforts on the development of organic batteries, their full potential is still not being realized. The individual components, such as electrode materials and electrolytes, are in most cases developed independently and are not adjusted to each other. In this context, we report on the performance optimization of a full-organic solid-state battery system by the mutual adaptation of the electrode materials and an ionic liquid (IL)-based gel polymer electrolyte (GPE). The formulation of the latter was designed for a one-step manufacturing approach and can be applied directly to the electrode surface, where it is UV-cured to yield the GPE without further post-treatment steps. Herein, a special focus was placed on the applicability in industrial processes. A first significant capacity increase was achieved by the incorporation of the IL into the electrode composite. Furthermore, the GPE composition was adapted applying acrylate- and methacrylate-based monomers and combinations thereof with the premise of a fast curing step. Furthermore, the amount of IL was varied, and all combinations were evaluated for their final performance in cells. The latter variation revealed that a high ionic conductivity is not the only determining factor for a good cell performance. Next to a sufficient conductivity, the interaction between electrode and electrolyte plays a key role for the cell performance as it enhances the accessibility of the counter ions to the redox-active sites. 相似文献
993.
贵金属物种(Rh或Ir络合物)在均相羰基化和氢甲酰化催化过程得到了广泛的应用,但始终存在分离繁琐等问题,其均相多相化可很大程度上简化分离操作,故一直广受重视.单位点催化剂因其具有可与均相相比拟的较高金属利用率和选择性而成为均相多相化的重要研究方向之一.研究发现,在碘物种存在的情况下用于固载金属物种的配位键容易断裂,进而导致金属物种的流失,而通过离子键固载的[Rh(CO)2I2]–物种更加稳定,比如著名的甲醇羰基化“AceticaTM”工艺中,[Rh(CO)2I2]–负一价阴离子物种是以离子键的方式固定在带有阳离子骨架的甲基化聚乙烯吡啶树脂上.与甲醇羰基化过程类似的乙醇羰基化过程是生产重要化工中间体丙酸的主要途径之一,但该过程的均相多相化始终存在着稳定性差这一关键问题.为了解决这一问题,基于之前将固载于季鏻盐聚合物的[Rh(CO)I3]2–应用于甲醇羰基化的工作,我们将类似的季鏻盐聚合物固载Rh基催化剂Rh-TPISP用于多相乙醇羰基化过程,通过多种表征进一步证明了Rh物种和P物种结构,并提出了“双离子键”模型.P的K边XANES证明了聚合物TPISP的季鏻化阳离子骨架特征.HAADF-STEM测试表明Rh-TPISP中的Rh呈现单位点分散的状态.Rh的XPS和XANES结果证明了Rh-TPISP中Rh物种的价态介于0~+1.通过EXAFS的拟合解析给出了[Rh(CO)I3]2–活性中心结构.由于[Rh(CO)2I2]–为经典的羰基化活性中心,为了进一步证明该结构的正确性,我们将Rh-TPISP的EXAFS和IR谱图与标样[PPh3Et]+[Rh(CO)2I2]–对比发现:在EXAFS谱图中,Rh-TPISP中的Rh-C峰高低于[PPh3Et]+[Rh(CO)2I2]–的Rh-C峰高,而Rh-TPISP中的Rh-I峰高高于[PPh3Et]+[Rh(CO)2I2]–的Rh-I峰高,这就说明Rh-TPISP中Rh物种的Rh-C配位数小于2,而Rh-I配位数大于2;在IR谱图中,标样[PPh3Et]+[Rh(CO)2I2]–中有两个羰基振动峰,与该物种的两个Rh-C配位键相符,而Rh-TPISP中的只有一个羰基振动峰,说明Rh-C配位数为1.因此,Rh-TPISP催化剂的季鏻盐骨架中的每个P物种带有一个正电荷,每个带有两个负电荷的[Rh(CO)I3]2–通过与两个[P]+的静电作用进行固载,形成“双离子键”结构.该催化剂在固定床乙醇羰基化过程中表现出优异的羰基化活性、选择性和稳定性.在3.5 MPa、195 oC反应近1000 h后,Rh-TPISP催化剂TOF保持在约350 h–1,丙酰基选择性为95%以上,高出所有文献报道的均相和多相乙醇羰基化活性.其较高的活性主要是因为[Rh(CO)I3]2–比传统Rh活性相[Rh(CO)2I2]–具有更强的富电子性,而较高的稳定性主要是由于“双离子键”这种强静电作用比“AceticaTM”工艺中“单离子键”更有利于Rh物种的固载.故Rh-TPISP催化剂中的“双离子键”对其优异的催化性能具有极其重要的作用,对后续多相乙醇羰基化的发展具有重要意义. 相似文献
994.
The different oxidation states of sulphur atom play a significant role on functional materials. In this work, a aryl-thioether and its sulphone substituted benzo[c][1,2,5]oxadiazole dyes were synthesized and utilized to determine thiol-containing amino acids. The result of selectivity experiments showed they detected the cysteine and homocysteine under physiological condition with negligible interference from other amino acids. In comparison to the thioether dye, the sulphone-based dye exhibited much faster response time for Cys and Hcy. However, the sulphone restricted its thiol-reactivity and bioimaging performance in living cells. By reducing the oxidation state of sulphur atom, we amazedly found that the sulfoxide-based dye still maintained high selectivity ultrafast response time for Cys/Hcy under physiological condition. It was worth mentioning that it also had high reactivity and good bioimaging performance that sulfone compounds did not have. 相似文献
995.
Both racemate and enantiomer of a novel double helix,binaphthylcyclooctaterthiophene(BN-COTh),which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds,have been synthesized with two building blocks,cycloocta-tetrathiophene(COTh) and cyclooctadinaphthyldithiophene(CONT) fused together via Negishi coupling reaction.Another homologue,dinaphthylcyclooctaterthiophene(DN-COTh) has been employed together as a model compound.Besides the synthetic work,BN-COTh and DN-COTh have been investigated by studying their crystal structures,spectroscopic behaviors,chiral resolution and chiral characteristics,including circular dichroism(CD) spectra and optical rotations.In addition,the novel crystal of enantiomer of(R,R,R)-BN-COTh has been explored.The enantiomer molecules packing along b-axis to form a larger and extended assembly packing due to intermolecular interactions between the enantiomer molecules and chloroform molecules in crystal. 相似文献
996.
Jing Sun Junsen Jia Bo Zhao Jingjing Yang Manjeet Singh Zhongfu An Hua Wang Bingshe Xu Wei Huang 《中国化学快报》2021,32(4):1367-1371
A purely organic D-π-A-π-D type emitter showing thermally activated delayed fluorescence(TADF) and room temperature phosphorescence(RTP) was designed and synthesized by utilizing the benzophenone as an acceptor and the N-phenyl-2-napthylamine as a donor moiety.It exhibits considerable TADF character in doped PMMA film and room temperature phosphorescence with a long lifetime of 74 ms at466 nm in solid state.The devices with the configuration of ITO/Mo_2 O_3(4 nm)/mCP(30 nm)/mCP:x wt%NP2 BP/TmTyPB(60 nm)/LiF(1.5 nm)/AI(100 nm) were prepared by vacuum evaporation to explore their electroluminescent performance.Intere stingly,the non-doped device has obtained near-white emission with a fluorescence emission peak at 475 nm and a phosphore scence emission peak at 563 nm having the CIE coordinate of(0.23,0.32) and the maximum external quantum efficiency of 1.09%. 相似文献
997.
Hyperbranched poly(glycidol) containing hydroxyl groups was firstly synthesized via anionic polymerization and then reacted with 2-bromoisobutyl bromide to form macroinitiator HPG-Br. Finally, a hyperbranched star polymer (HPG-PPEGMA) was successfully prepared by atom transfer radical polymerization (ATRP) of poly(ethylene glycol) methyl ether methacrylate using HPG-Br as macroinitiator. The structures and properties of the obtained polymers were characterized by 1H NMR, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The ionic conductivity of the polymer electrolytes composed of HPG-PPEGMA and lithium bis(trifluoromethanesulfonimide) (LiTFSI) was investigated via electrochemical impedance spectroscopy. The results showed that the room temperature ionic conductivity of the prepared hyperbranched star polymer electrolytes had a higher ionic conductivity. When [EO]/[Li] was 20, the ionic conductivity of the hyperbranched star polymer electrolyte was up to 1?×?10?4 Scm?1 at 30 °C. The onset decomposition temperature of the hyperbranched star polyether could reach 374 °C, indicating that the hyperbranched star polymer had a good thermal stability. The XRD results showed that the structure of the hyperbranched star polymer was beneficial to improve the ionic conductivity due to possessing a low degree of crystallinity. 相似文献
998.
999.
本文研究了在外电场下高分子的线性极化率和三阶非线性极化率,发现电子-电子相互作用使激子线性极化率χ(1)xx和三阶非线性极化率χ(3)xxxx都降低,而长程电子关联效应的作用更进一步降低χ(1)xx和χ(3)xxxx.准确地计算高分子聚合物的极化率可以更好的理解共轭聚合物的长程电子关联对有机分子线性和非线性响应的影响,确定其结构与非线性光学性质的关系. 相似文献
1000.
Development of Two‐Channel Phosphorescent Core–Shell Nanoprobe for Ratiometric and Time‐Resolved Luminescence Imaging of Intracellular Oxygen Levels
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