碳纳米管对天然有机质氯化消毒副产物生成的影响

以应用广泛的碳纳米材料多壁碳纳米管(CNTs)和水体中普遍存在的天然有机质(NOMs)为研究对象, 探讨CNTs对两种不同种类NOMs (Suwannee river standard humic acid, HASR和Suwannee river standard fulvic acid, FASR)氯化生成消毒副产物的影响。结果表明, 与单一NOMs体系相比, CNTs的存在会增加HASR和FASR氯化生成三卤甲烷(trihalomethanes, THMs)和卤代乙酸(halogenated acetic acid, HAAs)的产量和初始速率。这是由于CNTs和NOMs均可以作为消毒副产物的前体物, 混合体系中氯化反应活性位点数量增多, 因此产量和速率都有所提升。并且, 无论体系中是否存在CNTs, HASR生成THMs和HAAs的初始速率均高于FASR, 这是因为HASR的芳香共轭程度高于FASR, 更易与次氯酸反应。此外, 由于CNTs对HASR的吸附量高于FASR, 因此CNTs对HASR氯化生成消毒副产物的影响大于FASR。     

巴基纸制备的研究进展

作为一种功能化的多孔宏观结构,巴基纸既保留了纳米材料的物理化学特性,又有效解决了碳纳米材料个体操作应用困难的缺点,适合在复合材料、电极、催化、过滤和提纯等领域的大规模工程应用.按照所用碳纳米材料的不同,巴基纸大致可分为四类:单壁碳纳米管巴基纸、多壁碳纳米管巴基纸、碳纳米纤维巴基纸、混合巴基纸.按照其材料的不同对巴基纸的制备进行综述,并对将来的研究进行了展望.     

一维纳米结构太阳电池及其研究进展

一维纳米材料是一种新型的光伏材料,具有显著的二维量子限制效应、良好的光吸收特性和光学减反射特性,在改善太阳电池的光伏性能方面具有潜在应用.介绍了纳米线和纳米管等一维纳米结构的光吸收特性,重点评述了Si纳米线、GaAs纳米线和碳纳米管等一维纳米材料在太阳电池应用上的研究进展,同时指出了一维纳米结构太阳电池研究中存在的一些问题,并提出了其今后的发展方向,如优化工艺和电池组态形式、改善界面特性以及深入揭示一维纳米结构太阳电池的载流子输运机制等.     

竹节状CNTs/CdS核壳纳米线的制备与形态特征

以竹节状碳纳米管(CNTs)为模板,采用常温化学还原路线制备了CNTs/CdS核壳纳米线,用透射电子显微镜(TEM)观察了产物的微观形貌,用X射线衍射(XRD)技术分析了产物的物相,证实所得产物由CNTs与六方格子的CdS纳米晶体构成,具有核壳纳米线结构.研究发现CNTs竹节状的形态特点影响了得到的核壳结构的纳米线的微观形貌.在反应物浓度较低时,CdS晶体不像在侧壁平直的CNTs表面生长那样均匀包覆在CNTs表面,而是呈现根瘤状形貌;当反应物浓度升高时,CdS晶体均匀包覆在CNTs表面.当把还原反应时间缩短(如15m in),观察到CNTs环绕在CdS纳米晶体表面的新形态,推测这与CNTs的竹节状特殊形态有关.这些结果对于阐明CNTs/化合物半导体复合材料的形态结构控制原理和开发新材料具有重要参考价值.     

低维硼碳纳米材料第一原理研究

介绍了近年来关于低维硼碳纳米材料结构和电子性质的研究工作.通过第一原理计算,从理论上预言了稳定的低维硼纳米结构,并系统研究了以稳定硼平面为基础的硼纳米管和硼纳米带的电子性质.对于硼碳复合纳米材料,以BC3,BC5和BC7有序结构的平面为基础,发现对其剪裁、氢化修饰之后,硼碳纳米结构具有丰富的电磁学性质,可能在未来电子学器件中得到广泛的应用.     

石墨烯纳米带的制备方法

石墨烯纳米带(GNRs)是一种新型的一维碳纳米材料,因为它具有独特的尺寸效应、量子效应和界面效应等,使它在电子学和磁学方面有着巨大的应用前景.主要介绍了GNRs的两种制备方法:自上而下法和自下而上法.自上而下的制备方法重点描述解卷碳纳米管(CNTs)法、催化法和刻蚀法;自下而上的制备方法主要包括表面介导合成法和湿法有机合成等.     

糊精及聚乙二醇水溶液放电制备洋葱状富勒烯

考察了不同有机介质对制备碳纳米材料的影响,以糊精(C6H10O5)水溶液为放电介质,石墨做电极,成功制备了纳米洋葱状富勒烯(Onion-like Fullerenes:OLFs)和多壁碳纳米管.利用场发射扫描电子显微镜,高分辨透射电镜和X-射线衍射对所得产物进行了表征.结果表明:OLFs和多壁碳纳米管富含在阴极沉积物中且形貌规则,石墨化程度高;漂浮在糊精溶液表面的产物中没有OLFs和碳管的生成.以聚乙二醇水溶液为放电介质,未发现洋葱状富勒烯,但有大量的碳管和碳球存在,研究表明利用无毒有机介质水溶液制备碳纳米材料是可行的.     

低维氮化硼纳米材料

低维碳纳米材料的广泛研究,引起了人们对于纳米尺度范围内不同维度的同素异形体材料的极大关注.氮化硼纳米材料具有与碳纳米材料类似的结构,但具有完全不同的性质.不同于金属性和半导体性的碳纳米管,氮化硼纳米管是一种电绝缘体,其带隙不依赖于管子的几何构型,它具有高的热传导率、优异的化学稳定性和良好的机械性能.二维的氮化硼纳米薄膜具有同样的优点.这些独特的性能使得氮化硼纳米管和纳米薄膜在各种潜在的领域,如光电子器件、功能复合材料、储氢,催化等,具有重要的应用前景.本文概述了我们在一维氮化硼纳米管、二维氮化硼纳米薄膜方面的一些理论研究,包括氮化硼纳米管与单层材料的结构、缺陷、化学修饰、气体吸附以及三维氮化硼纳米超结构.     

平衡压力对碳纳米材料储氢的影响

燃料电池电动车需要高效、安全的储氢技术。采用体积法测定常温条件下氢气在自制的碳纳米材料 (碳纳米管和碳纳米纤维 )上的储存能力。研究发现 :在 2 5℃下 ,当平衡压力在 9～ 10 MPa之间时 ,氢气在碳纳米材料上有最大的吸附量 ,H与 C质量比为 3.1%。对此现象做了相应的解释 ,并对氢气在碳纳米材料中储存的原理作了初步的探讨。这将有助于进一步提高氢气在碳纳米材料中的储存能力 ,以利于最终实现碳纳米材料储氢技术在工程上的应用     

二维、三维模型碳纳米管场发射场强计算的比较研究

在计算碳纳米管场发射显示器中电场强度时,为了提高计算效率,许多资料将三维空间的场发射简化为二维模型进行计算,为了比较分析使用二维模型和三维模型计算结果的差异,建立了二维模型单根碳纳米管、三维模型单根碳纳米管和单碳纳米墙3个模型,应用Ansoft Maxwell有限元数值仿真软件进行了仿真,计算结果表明:二维碳纳米管场发射模型的仿真结果代表的三维空间实际情况为碳纳米墙场发射,而不是真正的三维空间碳纳米管场发射。对于单根碳纳米管,用二维模型计算的碳纳米管尖端电场强度仅为三维空间碳纳米管尖端电场强度的1／4。     

Advanced technology for functionalization of carbon nanotubes

Functionalization of carbon nanotubes (CNTs) has attracted considerable interest in the fields of physics, chemistry, material science and biology. The functionalized CNTs exhibit improved properties enabling facile fabrication of novel nanomaterials and nanodevices. Most of the functionalization approaches developed at present could be categorized into the covalent attachment of functional groups and the non-covalent adsorption of various functional molecules onto the surface of CNTs. This review highlights recent development and our work in functionalization of carbon nanotubes, leading to bio-compatible CNTs, fluorescent CNTs and transition metal functionalized CNTs. These novel methods possess advantages such as simplified technical procedures and reduced cost of novel nanomaterials and nanodevices fabrication.     

Carbon nanotubes in biology and medicine: An overview

Rapid development in the field of nanomedicine is bringing novel opportunities for improved disease diagnosis and drug delivery. Among various nanomaterials involved in nanomedicine, carbon nanotubes (CNTs) possessing a unique one-dimensional structure with interesting intrinsic mechanical, physical, and chemical properties have been extensively explored for a wide range of applications in biology and medicine. This review article provides an overview of how CNTs are used in different aspects of biomedicine including drug delivery and cancer treatment, bio-sensing, biomedical imaging, as well as tissue engineering. The recent developments, future perspective, and major challenges in this field are discussed.     

电泳沉积海藻酸钠/碳纳米管修饰高模碳纤维表面

采用纳米材料增加碳纤维（CF）的表面粗糙度及活性官能团,不仅可以改善CF增强复合材料的界面结合状态,而且不会对CF本体造成损伤,是一种极具发展潜力的新型CF表面改性手段。使用电泳沉积技术（EPD）将碳纳米管（CNTs）沉积在高模CF表面,然后与环氧树脂（EP）复合,制备了单向纤维增强层压板（CF/EP复合材料）。使用万能拉力机测试CF/EP复合材料的层间剪切强度（ILSS）,结果表明,在电压为6 V时制备的CF/EP复合材料的ILSS为58.9 MPa,与未经EPD处理的CF/EP复合材料（ILSS=52.2 MPa）相比提高了12.8%。同时,通过EPD制备了海藻酸钠与CNTs共沉积修饰的高模CF,海藻酸钠的加入增加了CNTs与CF表面的黏附性及氧含量,提高了纤维表面对树脂基体的浸润性。当CNTs的质量浓度为0.3 mg/mL、海藻酸钠的质量浓度为1 mg/mL、EPD电压为8 V时,所制备的CF/EP复合材料的ILSS可达68.3 MPa,与未经EPD处理的CF/EP复合材料相比提高了30.8%。     

电泳沉积海藻酸钠/碳纳米管修饰高模碳纤维表面

采用纳米材料增加碳纤维（CF）的表面粗糙度及活性官能团,不仅可以改善CF增强复合材料的界面结合状态,而且不会对CF本体造成损伤,是一种极具发展潜力的新型CF表面改性手段。使用电泳沉积技术（EPD）将碳纳米管（CNTs）沉积在高模CF表面,然后与环氧树脂（EP）复合,制备了单向纤维增强层压板（CF/EP复合材料）。使用万能拉力机测试CF/EP复合材料的层间剪切强度（ILSS）,结果表明,在电压为6 V时制备的CF/EP复合材料的ILSS为58.9 MPa,与未经EPD处理的CF/EP复合材料（ILSS=52.2 MPa）相比提高了12.8%。同时,通过EPD制备了海藻酸钠与CNTs共沉积修饰的高模CF,海藻酸钠的加入增加了CNTs与CF表面的黏附性及氧含量,提高了纤维表面对树脂基体的浸润性。当CNTs的质量浓度为0.3 mg/mL、海藻酸钠的质量浓度为1 mg/mL、EPD电压为8 V时,所制备的CF/EP复合材料的ILSS可达68.3 MPa,与未经EPD处理的CF/EP复合材料相比提高了30.8%。     

A review of the large-scale production of carbon nanotubes: The practice of nanoscale process engineering

Carbon nanotubes (CNTs) are nanomaterials that have attracted great research interest because of their unique properties and promising applications. The controllable synthesis of CNTs is a precondition for their broad application. In this review, we consider nanoscale process engineering and assess recent progress in the mass production of ultra-long, inexpensive CNTs with good alignment as well as tunability in wall number and diameter for fundamental and engineering science applications across multiple scales. Cutting-edge nanoscale process engineering research in the areas of physics, chemistry, materials, engineering, ecology, and social science will allow us to obtain high added value and multi-functional advanced CNTs. The synthesis of CNTs with controllable chirality, good-alignment, and predetermined sizes and lengths still presents great challenges. Through multidisciplinary scientific research, advanced CNT-based materials will promote the development of a sustainable society.     

碳纳米管在碳纤维纸上的生长研究

采用酞菁铁(FePc)作为碳源和催化剂源,利用化学气相沉积(CVD)法在碳纤维纸(CFP)上生长碳纳米管(CNTs),从而制备了碳纳米管/碳纤维纸复合材料,并利用扫描电镜(SEM)测试、X射线衍射(XRD)测试、接触角测试、电导率测试和孔隙率测试等方法对其结构和性能进行了表征.结果表明,碳纳米管能在碳纤维纸表面生长;表面生长碳纳米管后,碳纤维纸的疏水性、孔隙率和电导率均有所提高.     

Patterned deposition of multi-walled carbon nanotubes on self-assembled monolayers

The excellent electro-mechanical properties and chemical stability of CNTs promise a prospective ap- plications in nanotechnology. For electronic applica- tions, CNTs have been proved successful in practice in producing components such as a junction and f…     

碳纳米管的表面修饰及其在水中的分散性能研究

采用硫酸和硝酸混合酸对催化裂解法(CⅧ法)制备的多壁碳纳米管(CNTs)进行纯化，然后运用十六烷基三甲基溴化胺(HTAB)对CNTs进行修饰，并利用透射电子显微镜、红外光谱和拉曼光谱表征了CNTs的表面结构；另外，通过数码照相机和乌氏粘度计研究了修饰的CNTs在水中的分散性能，实验结果表明，通过混合酸处理能够使CNTS表面拥有较多的羟基和羧基官能团；在氨水的作用下，CNTs能够被HTAB所包覆，而且修饰后的CNTs在水中的分散性能得到提高．     

Effects of Temperature and Catalyst Concentration on the Growth of Aligned Carbon Nanotubes

The effects of preheating and pyrolysis temperatures and catalyst concentration on the synthesis of aligned carbon nanotubes （CNTs） using ferrocene as the catalyst and xylene as the carbon source in chemical vapor deposition were experimentally studied. The as-grown aligned CNTs were characterized by field emission scanning electron microscopy, transmission electronic microscopy, high-resolution transmission electronic microscopy, and Raman spectroscopy. The growth rate, the diameters, and the degree of crystal structure of the aligned CNTs were all found to depend on the preheating and pyrolysis temperatures and the catalyst concentration. The optimized conditions for the growth of aligned CNTs resulted in a rapid growth rate of 20.4 um/min, with the CNTs having a good, uniform crystal structure, and clean surfaces with little amorphous carbon. The results also show that higher preheating temperatures and lower ferrocene concentrations favor the growth of single-walled CNTs.     

Modifying the poly ether ester antistatic agent by carbon nanotubes, the antistatic effect on polypropylene fibers

A new antistatic fiber is investigated using carbon nanotubes (CNTs) to enhance the antistatic ability of polymer fibers based on the mechanism of the discharging process of polarity macromolecule. Composite antistatic agent (CAA), prepared by dispersing CNTs in an organic antistatic agent carrier containing metallic ions in their main chains, is cospun with polypropylene (PP) to prepare CAA/PP fibers. It is indicated through analyzing the measured dynamic tribo-electrostatic voltages that CNTs can promote the discharging process of polarity macromolecule of antistatic agent carrier and further improve the antistatic ability of PP fibers. It is also indicated that the antistatic effect promoted by CNTs is better than that by conductive carbon black. Moreover, the antistatic effects of the CNTs treated by different methods are also compared.