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聚苯胺理论比容量高、易合成,是一种理想的电极材料,但其循环寿命差,而石墨烯具有高的理论比表面积,将二者复合,充分利用两者之间的协同效应,能够使复合材料具有优异的电化学电容性能。本文回顾了近几年石墨烯-聚苯胺纳米复合材料在超级电容器中的最新研究结果及其制备方法,并对如何优化电极的结构与性能进行讨论,同时介绍了石墨烯-聚苯胺类电极材料在有机超级电容器中的应用进展,最后对石墨烯-聚苯胺复合材料的前景进行了展望。超级电容器用石墨烯-聚苯胺纳米复合材料的发展取决于其合理的微观结构设计,构建理想的三维多孔结构以避免聚苯胺的膨胀与收缩现象是研究的方向之一,此外,在改善石墨烯和聚苯胺间弱的界面相互作用的同时寻求石墨烯性能与功能化的平衡仍是难点,机械性能优异的聚苯胺纳米复合材料对于柔性全固态超级电容器的研究也会起到关键作用。 相似文献
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原位溶液聚合聚苯胺与聚苯乙烯溶液共混复合材料的制备及表征 总被引:2,自引:0,他引:2
以DNSA掺杂剂,在醇(或酮)-水介质中采用原位溶液聚合法制备出了聚苯胺,以溶液共混法制备出了聚苯胺/聚苯乙烯复合材料,采用红外光谱、热失重、元素分析、扫描电镜对产物进行了表征。结果显示:掺杂的聚苯胺电导率最高为0.65 S/cm,优于常用的DBSA,具有一定实用价值和理论意义。该复合材料表面电阻率最低为101Ω/□数量级,并在一定范围内可调,可用于电磁屏蔽,适合于聚合物表面使用。 相似文献
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通过原位聚合的方式在银纳米粒子/多壁碳纳米管(Ag/MWCNT)复合材料的表面成功聚合苯胺单体制备了聚苯胺/银纳米粒子/多壁碳纳米管(PANI/Ag/MWCNT)三元复合材料苯.通过对三元复合材料的结构以及表面形貌进行分析,表明聚苯胺层完全包覆了Ag/MWCNT复合材料,形成了核壳式结构.同时银纳米粒子则以单质晶体的形态存在于多壁碳纳米管与聚苯胺层之间.三元复合材料电极在1 mol/L的KOH溶液中具有极低的阻抗,而与聚苯胺电极相比,这些复合材料电极则表现出更低的电阻、更高的电化学活性和更好的循环稳定性.尤其是当苯胺和Ag:MWCNTs质量比为5:5时,该复合材料电极在0.25 A/g的电流密度下表现出最大的比电容值为160 F/g. 相似文献
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强磁场作用对聚苯胺颗粒形貌及电性能的影响 总被引:15,自引:1,他引:14
聚苯胺的聚合掺杂条件对其颗粒结构及其导电性能有着很大的影响. 本文在10 T强磁场的作用下用化学氧化溶液原位聚合法得到聚苯胺并观察充分聚合后聚苯胺的颗粒结构、形貌特征及与其形成复合材料的电性能. 实验表明, 在没有强磁场作用下掺杂聚苯胺颗粒呈现礁石状, 而强磁场作用下的原位聚合聚苯胺颗粒呈现直径大约50 nm的棒状, 但其复合材料的电阻率与没有强磁场相比高出3个数量级; 本征态聚苯胺在强磁场下再掺杂得到20~30 nm的球状颗粒, 其复合材料电阻率却降低1个数量级. 分析认为这主要由于强磁场对聚苯胺晶粒的取向作用以及强磁场对聚合掺杂过程的影响所至. 相似文献
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聚苯胺是目前研究最为广泛的导电高分子材料之一,具有特殊的电学、光学性能,在电子工业、信息工程、国防工程等的应用开发进行了深入研究。聚苯胺经掺杂后可形成P型和N型导电态,这种掺杂机制使得聚苯胺的掺杂和脱掺杂完全可逆,而掺杂度受pH值和电位等因素的影响,且电化学活性同比传统锂电极材料在充放电过程中具有更优异的可逆性能,因此有关在设计聚苯胺参与锂电池电极复合材料的研究也越来越受到重视。本文综述了不同结构聚苯胺锂离子电池复合材料的制备方法,并着重介绍了聚苯胺基复合材料锂离子电池等领域研究的电化学性能,最后展望了聚苯胺基复合材料的应用前景。 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献