生物分子功能化碳纳米管

利用生物分子功能化碳纳米管,使其具备生物相容性和特殊的识别功能并引入生物体系是一项极具应用潜力的研究.如何利用不同种类的生物分子功能化碳纳米管则是该领域须解决的一个关键问题.本文综述了利用生物分子酶、蛋白质、氨基酸、肽螺旋、DNA功能化碳纳米管的最新研究进展,重点介绍了碳纳米管侧壁与端口的DNA功能化以及碳纳米管的DNA填充,并对DNA功能化碳纳米管在生物传感器、电化学检测及DNA操纵碳纳米管自组装方面的应用作了阐述.     

碳纳米管共价功能化*

碳纳米管由于其独特的结构与优异的各项性能,在许多领域具有巨大的应用潜力,已引起了广泛的关注。由于碳纳米管不溶于水和有机溶剂,极大地制约了其性能应用,因此碳纳米管的功能化就成为目前研究的热点。本文侧重于碳纳米管的共价功能化,详细讨论了碳纳米管不同位置共价功能化的研究进展。     

共价功能化碳纳米管的应用研究进展

本文跟踪碳纳米管的功能化研究进展,对共价功能化碳纳米管在材料领域,如复合材料、催化剂载体、电子器件、光学材料、及生物医学中的应用进行了综述.     

功能化碳纳米管的电磁性能研究及进展

碳纳米管是最近发展起来的一种结构独特,性能优异的新材料,已成为当今物理、化学、材料等领域共同关注的课题.而碳纳米管的功能化更是为我们开辟了一个广阔的研究领域.本文总结了近十多年来功能化碳纳米管的研究进展,并侧重对功能化碳管的合成方法及电磁特性以及应用进行了评述.     

运用功能化修饰的碳纳米管针尖测量配体-受体的作用力

电弧法自制碳纳米管原子力显微镜针尖,对其末端进行功能化修饰,然后测量配体-受体之间的作用力。运用没有功能化修饰的碳纳米管针尖与修饰有亲和素分子的基底进行接触测量时,没有粘滞力出现;而运用末端修饰生物素分子的碳纳米管针尖测量时,有粘滞力产生。功能化的碳纳米管针尖直接测得的粘滞力均大约200pN,此值符合一对配体生物素和受体亲和素之间的作用力。这一结果很难用传统的针尖获得,功能化修饰的碳纳米管针尖能够克服传统针尖在力测量中的局限,在生物学和化学领域有着广泛的应用前景。     

基于碳纳米管的化学修饰电极及电化学生物传感器的研究进展

综述了碳纳米管的结构、合成、纯化、功能化、分散及基于碳纳米管的化学修饰电极和电化学生物传感器的研究进展。     

功能化碳纳米管作为固体碱用于Knoevenagel缩合

采用液相沉积方法分别制备了聚乙烯亚胺功能化和聚4-乙烯基吡啶功能化的碳纳米管催化剂,利用N2吸附/脱附、透射电子显微镜(TEM)、热重分析(TG)以及酸碱滴定等方法对所得催化剂的结构和碱性进行了表征,测试了其对于苯甲醛和丙二腈的Knoevenagel缩合反应的催化性能。结果发现,聚乙烯亚胺功能化的碳纳米管具有比聚4-乙烯基吡啶功能化的催化剂更高的碱催化能力。对碳纳米管进行强酸预处理可增加其与修饰剂的相互作用,虽然会降低其碱催化活性,但却可使其稳定性大大提高。     

功能化碳纳米管与四苯基锌卟啉轴向配位组装(英文)

本文报道了一种基于四苯基锌卟啉与含吡啶基功能化多壁碳纳米管经轴向配位组装。它们被红外光谱、拉曼光谱和透射电镜所表征。荧光光谱研究表明,在该体系中功能化多壁碳纳米管能有效地淬灭卟啉的荧光。     

功能化碳纳米管作为固体碱用于Knoevenagel缩合

采用液相沉积方法分别制备了聚乙烯亚胺功能化和聚4-乙烯基吡啶功能化的碳纳米管催化剂,利用N₂吸附/脱附、透射电子显微镜（TEM）、热重分析（TG）以及酸碱滴定等方法对所得催化剂的结构和碱性进行了表征,测试了其对于苯甲醛和丙二腈的Knoevenagel缩合反应的催化性能。结果发现,聚乙烯亚胺功能化的碳纳米管具有比聚4-乙烯基吡啶功能化的催化剂更高的碱催化能力。对碳纳米管进行强酸预处理可增加其与修饰剂的相互作用,虽然会降低其碱催化活性,但却可使其稳定性大大提高。     

苯环共价功能化碳纳米管电性理论研究

通过4种键连方式将苯环共价连接到超晶胞为1×1×3的锯齿型单壁碳纳米管CNT(8,0)上.在密度泛函理论基础上,通过Siesta软件计算苯环共价功能化碳纳米管的几何结构、能带结构、态密度和波函数,分析键连方式对碳纳米管电性的影响.结果表明苯环通过4种键连方式共价功能化的碳纳米管都是在Γ点具有直接带隙的半导体.其中直接键连和酰胺键连得到的苯环功能化碳纳米管在费米能级附近产生杂质带,比纯CNT带隙减小约0.4e V.而通过2个亚甲基键连和吡咯烷键连2种方式功能化的碳纳米管,其带隙仅比纯CNT带隙减小0.1~0.15e V.     

NEXAFS光谱分析聚合物修饰的单壁碳纳米管

利用C1s、O1s、N1s近边X射线吸收精细结构(Near Edge X-Ray Absorption Fine Structure,NEXAFS)光谱对聚合物修饰的碳纳米管进行了分析,研究了氧化及偶联聚合物对碳纳米管结构的影响。氧化碳纳米管及十八胺修饰的、聚合物/十八胺双修饰的碳纳米管的NEXAFS光谱均出现了碳/氧K边π*(C=O)和σ*(C-O)共振峰;而十八胺修饰的、聚合物/十八胺双修饰的碳纳米管则出现了氮K边π*(N-C=O)和σ*(N1s)共振峰。分析表明,NEXAFS光谱可有效表征聚合物修饰的碳纳米管。     

Preparation and Characterization of Poly(methyl methacrylate)-functionalized Carboxyl Multi-wall Carbon Nanotubes

"An in situ polymerization process was used to prepare poly (methyl methacrylate) (PMMA)-functionalized carboxyl multi-walled carbon nanotubes using carboxylate carbon nanotubes and methyl methacrylate as reactants and benzoyl peroxide as an initiator agent. The functionalized multi-walled carbon nanotubes were characterized using transmission electron microscope, scanning electron microscope, nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis and Raman. The results indicate that the PMMA chains are covalently linked with the surface of carboxylate carbon nanotubes. The surface morphology is controlled by the content of carboxylate carbon nanotubes in the reactants. The PMMA functionalized multi-walled carbon nanotubes are soluble in deuterated chloroform. The storage modulus and tanffi magnitude increase as the content of CCNTs increases up to 0.3%."     

Preparation of Amino-functionalized Multiwall Carbon Nanotube/Gold Nanoparticle Composites

Multiwall carbon nanotubes (MWNT) were modified orderly with carboxyl groups and amino groups. The MWNT/gold nanoparticle composites were formed when the amino‐functionalized MWNT was interacted with gold colloids. The functionalized MWNT was characterized using Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy. The amino‐functionalized MWNT allows further attaching gold nanoparticles through electrostatic interaction between the negatively charged gold nanoparticles and amino groups on the surface of the MWNT. The composite of gold nanoprticles and amino‐functionalized MWNT was characterized by transmission electron microscopy. This method decorating carbon nanotubes can be used to identify the location of functional groups, i.e. defect sites on carbon nanotubes.     

Highly Hydrophobic Conducting Nanocomposites Based on a Fluoropolymer with Carbon Nanotubes

A procedure was suggested for preparing highly hydrophobic conducting coatings based on fluoropolymers with carbon nanotubes of two types: Taunit-MD and carbon nanotubes functionalized with alkyl groups. The surface resistance, contact angle, sliding angle, and surface roughness were measured; structural features of the nanocomposites were studied. The properties of the coatings obtained depend on the concentration and type of the carbon nanotubes used. Introduction of functionalized carbon nanotubes into a fluoropolymer matrix allows preparation of coatings with higher values of the sliding angle and electrical resistance. The contact angle and sliding angle depend on the surface roughness and structure in different fashions.     

Enhanced preconcentration of selected chlorofluorocarbons on multiwalled carbon nanotubes with polar functionalities

Chromatographic monitoring of chlorofluorocarbons in air requires the preconcentration of these highly volatile species. In this paper, we present functionalized multiwalled carbon nanotubes as effective sorbents for a microtrap designed for chlorofluorocarbons preconcentration. Among the commercial carbons and carbon nanotubes studied, functionalization via carboxylation and propyl amine was most effective for dichlorofluoromethane and trichlorofluoromethane (Freon 11), which were selected as representative chlorofluorocarbons. The results show that carbon nanotubes functionalized with a polar groups led to as much as a 300% increase in breakthrough volume and the desorption bandwidth was reduced by 2.5 times.     

Designing novel materials through functionalization of carbon nanotubes for application in nuclear waste management: speciation of uranyl

Understanding the behavior of radioactive nuclide elements in different environmental conditions is an active area of research. In this work, we have investigated the possible interaction mechanism between carbon nanotubes and uranyl using density functional theory. It is shown that functionalized carbon nanotubes can be used to bind uranyl ions much more efficiently as compared to their unfunctionalized counterpart. The uranyl binding energies are sensitive to the nature of the functional groups rather than the carbon nanotube itself. The binding takes place preferably at the functionalized sites, although pH could determine the strength of uranyl binding. Our predicted results correlate well with the recent experimental uranyl sorption studies on carbon nanotubes. These finding are new and can open up a new era for actinide speciation and separation chemistry using carbon nanotubes.     

Polymer-masking for controlled functionalization of carbon nanotubes

An effective and versatile method for tube-length-specific functionalization of carbon nanotubes through a controllable embedment of vertically-aligned carbon nanotubes into polymer matrices is reported, which allows not only asymmetric functionalization of nanotube sidewalls, but also facile introduction of new properties (e.g. magnetic) onto the region-selectively functionalized carbon nanotubes.     

Carbon nanotubes with covalently linked porphyrin antennae: photoinduced electron transfer

Single- and multiwalled carbon nanotubes have been covalently functionalized with free-base porphyrin. The quantity of porphyrin linked to the surface was determined from thermogravimetric and UV-vis analysis. A reversible protonation equilibrium between the attached porphyrin and the residual acid groups of the carbon nanotubes has been identified. Steady-state fluorescence emission spectrum of the solutions of porphyrin-linked carbon nanotubes shows that the porphyrins act as energy absorbing and electron transferring antennae, and the carbon nanotubes act as efficient electron acceptors. The porphyrin-linked carbon nanotubes show 95-100% emission quenching, indicating a fast photoinduced electron transfer.     

卟啉修饰的碳纳米管研究进展

从问题解决的视角介绍碳纳米管的性质和在应用方面存在的问题。重点介绍卟啉修饰的碳纳米管的优势以及卟啉修饰碳纳米管的方法、应用和近期的研究进展。