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单壁碳纳米管在原子尺度的结构变化即可导致其电学、光学方面等性质的多样性和非连续的变化——如电学性质上可呈现半导体性或金属性。然而,在单壁碳纳米管表现出诸多优异性能的同时,如何实现碳纳米管的结构控制制备仍面临严峻的挑战。本文以单壁碳纳米管的管径、导电属性和手性控制为目标,介绍单壁碳纳米管的结构控制生长方法,主要包括温度扰动法、金属催化剂结构设计法、生长气氛调控法、外场辅助法、基底诱导法、非金属粒子催化法和sp2碳结构模板法等。并在此基础上总结了单壁碳纳米管结构控制生长的基本思路及实现途径,以期为后续单壁碳纳米管的规模化应用奠定基础。 相似文献
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结合DNA酶优异的氧化还原催化特性和碳纳米管的电化学特性, 制备了单壁碳纳米管-DNA酶复合材料, 并通过壳聚糖将其固定到玻碳电极表面构建了电化学生物传感界面. 研究了单壁碳纳米管-DNA酶复合结构的氧化还原反应催化特性, 并以此为传感平台构建了葡萄糖氧化酶电化学生物传感器. 结果表明, 单壁碳纳米管-DNA酶复合材料修饰的电极对过氧化氢的响应具有较宽的线性范围(5×10-6~1×10-2 mol/L)和良好的检测灵敏度(检出限为1×10-6 mol/L). 采用制备的葡萄糖氧化酶传感器实现了对葡萄糖的快速灵敏检测. 相似文献
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聚苯乙烯修饰碳纳米管表面的研究 总被引:4,自引:0,他引:4
利用原子转移自由基聚合方法合成了端基具有一个卤素的聚苯乙烯, 并通过叠氮化反应得到端基为叠氮基团的聚苯乙烯. 利用叠氮基与单壁或复壁碳纳米管的反应, 将聚苯乙烯接到碳纳米管的表面上, 实现了碳纳米管的化学修饰. 通过FTIR, XPS, TEM, UV和Raman光谱等技术证明了聚苯乙烯以共价键形式结合到碳纳米管表面上. 利用TGA估算出连接在碳纳米管上的聚苯乙烯的含量, 并推测出复壁碳纳米管中较多的结构缺陷更有利于聚合物的接枝. 相似文献
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采用直流电弧法制备单壁碳纳米管样品,用457.5和632.8nm两种不同的激发光分别测得单壁碳纳米管的正常拉曼光谱和共振拉曼光谱.通过理论分析得到了单壁碳纳米管的直径分布,进一步推测了其类型及结构参数;对单壁碳纳米管的正切拉伸模的成分进行了归属.在632.8nm激发波长下得到了IG/ID值随激光功率变化的曲线,认为在2.5mW时,单壁碳纳米管缺陷的结构可能发生了改变.在用457.5nm波长激发的单壁碳纳米管的拉曼光谱中,首次发现了1421cm-1的拉曼谱峰. 相似文献
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Wunderlich D Hauke F Hirsch A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(5):1607-1614
Covalent sidewall addition to single-walled nanotubes (SWNTs) of a series of organolithium and organomagnesium compounds (nBuLi, tBuLi, EtLi, nHexLi, nBuMgCl, tBuMgCl) followed by reoxidation is reported. The functionalized R(n)-SWNTs were characterized by Raman and NIR emission spectroscopy. The reaction of SWNTs with organolithium and magnesium compounds exhibits pronounced selectivity: in general, metallic tubes are more reactive than semiconducting ones. The reactivity of SWNTs toward the addition of organometallic compounds is inversely proportional to the diameter of the tubes. This was determined simultaneously and independently for both metallic and semiconducting SWNTs. The reactivity also depends on the steric demands of the addend. Binding of the bulky t-butyl addend is less favorable than addition of primary alkyl groups. Significantly, although tBuLi is less reactive than, for example, nBuLi, it is less selective toward the preferred reaction with metallic tubes. This unexpected behavior is explained by fast electron transfer to the metallic SWNTs having low-lying electronic states close to the Fermi level, a competitive initial process. The NIR emission of weakly functionalized semiconducting SWNTs, also reported for the first time, implies interesting applications of functionalized tubes as novel fluorescent reporter molecules. 相似文献
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Liang F Alemany LB Beach JM Billups WE 《Journal of the American Chemical Society》2005,127(40):13941-13948
Alkylation of nanotube salts prepared using either lithium, sodium, or potassium in liquid ammonia yields sidewall-functionalized nanotubes that are soluble in organic solvents. Atomic force microscopy and transmission electron microscopy studies of dodecylated SWNTs prepared from HiPco nanotubes and 1-iodododecane show that extensive debundling results from intercalation of the alkali metal into the SWNT ropes. TGA-FTIR analyses of samples prepared from the different metals revealed radically different thermal behavior during detachment of the dodecyl groups. The SWNTs prepared using lithium can be converted into the pristine SWNTs at 180-330 degrees C, whereas the dodecylated SWNTs prepared using sodium require a much higher temperature (380-530 degrees C) for dealkylation. SWNTs prepared using potassium behave differently, leading to detachment of the alkyl groups over the temperature range 180-500 degrees C. These differences can be observed by analysis of the solid-state 13C NMR spectra of the dodecylated SWNTs that have been prepared using the different alkali metals and may indicate differences in the relative amounts of 1,2- and 1,4-addition of the alkyl groups. 相似文献
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Saini RK Chiang IW Peng H Smalley RE Billups WE Hauge RH Margrave JL 《Journal of the American Chemical Society》2003,125(12):3617-3621
Alkyllithium reagents may be used to attach alkyl groups to the sidewalls of fluoro nanotubes. Thermal gravimetric analysis combined with UV-vis-Nir spectroscopy has been used to provide a quantitative measure of the degree of functionalization. SWNTs prepared using the HiPco process exhibit a higher degree of alkylation than SWNTs from the laser-oven method, indicating that the smaller diameter fluoro tubes are alkylated more readily. The spectral signature of the pristine SWNTs can be regenerated when the alkylated SWNTs are heated in Ar at 500 degrees C, demonstrating that dealkylation occurs at this temperature. TGA-MS analysis using a sample of n-butylated h-SWNTs showed that 1-butene and n-butane are formed during thermolysis. 相似文献
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Ozawa H Fujigaya T Niidome Y Hotta N Fujiki M Nakashima N 《Journal of the American Chemical Society》2011,133(8):2651-2657
Single-walled carbon nanotubes (SWNTs) have remarkable and unique electronic, mechanical, and thermal properties, which are closely related to their chiralities; thus, the chirality-selective recognition/extraction of the SWNTs is one of the central issues in nanotube science. However, any rational materials design enabling one to efficiently extract/solubilize pure SWNT with a desired chirality has yet not been demonstrated. Herein we report that certain chiral polyfluorene copolymers can well-recognize SWNTs with a certain chirality preferentially, leading to solubilization of specific chiral SWNTs. The chiral copolymers were prepared by the Ni(0)-catalyzed Yamamoto coupling reaction of 2,7-dibromo-9,9-di-n-decylfluorene and 2,7-dibromo-9,9-bis[(S)-(+)-2-methylbutyl]fluorene comonomers. The selectivity of the SWNT chirality was mainly determined by the relative fraction of the achiral and chiral side groups. By a molecular mechanics simulation, the cooperative interaction between the fluorene moiety, alkyl side chain, and graphene wall were responsible for the recognition/dissolution ability of SWNT chirality. This is a first example describing the rational design and synthesis of novel fluorene-based copolymers toward the recognition/extraction of targeted (n,?m) chirality of the SWNTs. 相似文献
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Free radicals generated by decomposition of benzoyl peroxide in the presence of alkyl iodides have been used to derivatize small-diameter single-wall carbon nanotubes (HiPco tubes). The degree of functionalization, estimated by thermal gravimetric analysis, is as high as 1 in approximately 5 carbons in the nanotube framework. The derivatized nanotubes exhibits remarkably improved solubility in organic solvents. The attached groups can be removed by heating in an atmosphere of argon. Derivatization was also accomplished by treating SWNTs with various sulfoxides employing Fenton's reagent. [reaction: see text] 相似文献
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Selective interactions of porphyrins with semiconducting single-walled carbon nanotubes 总被引:6,自引:0,他引:6
Li H Zhou B Lin Y Gu L Wang W Fernando KA Kumar S Allard LF Sun YP 《Journal of the American Chemical Society》2004,126(4):1014-1015
A derivatized porphyrin with long alkyl chains, 5,10,15,20-tetrakis(hexadecyloxyphenyl)-21H,23H-porphine, is selective toward semiconducting single-walled carbon nanotubes (SWNTs) in presumably noncovalent interactions, resulting in significantly enriched semiconducting SWNTs in the solubilized sample and predominantly metallic SWNTs in the residual solid sample according to Raman, near-IR absorption, and bulk conductivity characterizations. 相似文献
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Chattopadhyay J Sadana AK Liang F Beach JM Xiao Y Hauge RH Billups WE 《Organic letters》2005,7(19):4067-4069
[reaction: see text] Carbon nanotube salts prepared by treating single-wall carbon nanotubes (SWNTs) with lithium in liquid ammonia react readily with aryl iodides to give SWNTs functionalized by aryl groups. 相似文献
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Functionalization of single-walled carbon nanotubes with well-defined polystyrene by "click" coupling 总被引:3,自引:0,他引:3
Covalent functionalization of alkyne-decorated SWNTs with well-defined, azide-terminated polystyrene polymers was accomplished by the Cu(I)-catalyzed [3 + 2] Huisgen cycloaddition. This reaction was found to be extremely efficient in producing organosoluble polymer-nanotube conjugates, even at relatively low reaction temperatures (60 degrees C) and short reaction times (24 h). The reaction was found to be most effective when a CuI catalyst was employed in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene as an additive. IR spectroscopy was utilized to follow the introduction and consumption of alkyne groups on the SWNTs, and Raman spectroscopy evidenced the conversion of a high proportion of sp(2) carbons to sp(3) hybridization during alkyne introduction. Thermogravimetric analysis indicated that the polymer-functionalized SWNTs consisted of 45% polymer, amounting to approximately one polymer chain for every 200-700 carbons of the nanotubes, depending on polymer molecular weight. Transmission electron microscopy and atomic force microscopy were utilized to image polymer-functionalized SWNTs, showing relatively uniform polymer coatings present on the surface of individual, debundled nanotubes. 相似文献
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[reaction: see text] Pristine single-walled carbon nanotubes (SWNTs) and nucleotides mixed using a mechanochemical high-speed vibration milling technique (HSVM) are soluble in an aqueous solution, and the solubilities of SWNTs depend significantly on the number of phosphate groups and the kinds of bases employed. 相似文献
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Itaru Natori Shizue Natori 《Journal of polymer science. Part A, Polymer chemistry》2012,50(17):3682-3689
The first‐ever grafting of poly(1,3‐cyclohexadiene) (PCHD) onto single‐walled carbon nanotubes (SWNTs) was accomplished by reaction with poly(1,3‐cyclohexadienyl)lithium. The rate of this reaction was especially slow due to the heterogeneous nature of the reaction system. The concentration of active carbons available for reaction with PCHDLi on the solid surface of the SWNTs was found to be approximately 2.0 mol %. The mass of PCHD attached to the SWNTs was effectively controlled by varying the molecular weight of the PCHD. The resulting PCHD‐grafted SWNTs exhibited excellent solubility in organic solvent, maintaining a highly stable homogeneous dispersion even after 3 months. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献