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Dissertations / Theses on the topic 'Single-wall carbon nanotubes'

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Published: 4 June 2021

Last updated: 6 September 2023

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1

Sirdeshmukh, Ranjani. "Biological functionalization of single-wall carbon nanotubes." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 0.97Mb, 59 p, 2005. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1428206.

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2

Holt, Brian D. "Cellular Processing of Single Wall Carbon Nanotubes." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/397.

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Nanostructured materials are hailed to be the solutions of the future for many research areas, and single wall carbon nanotubes (SWCNTs) are one of the more interesting materials due to their highly desirable electronic, optical, thermal and mechanical properties. For instance, this combination of properties is of wide interest for biological applications, including cellular technologies. However, understanding cellular processing of SWCNTs is limited. In this thesis, quantification of sub-cellular events–including SWCNT uptake rates, altered mitosis, redistribution of sub-cellular components and reduced cellular functionalities–is used to formulate insight into how cells internalize and process SWCNTs. By understanding sub-cellular processing of SWCNTs, new basic science endeavors and SWCNT-based biological applications can be more effectively developed, and the insights can be generalized to other nanostructured materials.

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3

Son, HyungBin 1981. "Raman spectroscopy of single wall carbon nanotubes." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44725.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
Includes bibliographical references (p. 71-76).
A single wall carbon nanotube (SWNT) is a new form of carbon, whose atomic arrangement is equivalent to a graphene sheet rolled into a cylinder in a seamless way. The typical diameter of a SWNT ranges from 0.6 nm to several nm and the typical length ranges from tens of nm to several cm. Due to its small diameter and high aspect ratio, a SWNT has very unique electronic and vibrational properties. The goals of this thesis work are to design and construct a Raman instrument capable of obtaining signals from many different types of individual SWNTs, to develop methods and tools to collect, organize and analyze large amounts of Raman spectra from them, to use resonant Raman spectroscopy to characterize individual SWNTs, and to investigate how their electronic and vibrational properties change under various conditions, such as strain, or different substrate interactions. A high-efficiency widely-tunable Raman instrument is developed for the study of SWNTs. The environmental effects on the electronic and vibrational properties are investigated by suspended SWNTs. Using the high-efficiency Raman instrument, weak optical transitions of metallic SWNTs are found. The effect of strain on the vibrational mode frequencies of SWNTs are studied.
by Hyungbin Son.
Ph.D.

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4

Crisan, Alina Dora. "Non-collinear magnetoeletronics in single wall carbon nanotubes." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00976618.

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Recent developments in the field of nanotechnology allowed the access to adequate length scale necesary to closely investigate spins and opened large prospects of using electrons spin degree of freedom in new generation electronic devices. This have lead to the development of a vibrant field dubbed spintronics.Here, we present experiments that combine two very promising materials: namely cardon nanotubes and palladium-nickel (PdNi), with the purpose to manipulate the electronic spin both in the classical and in the quantum regime. We implement a quantum dot connected to two non-collinear ferromagnetic leads that acts as a spin-valve device. The versatility of carbon nanotubes to fabricate quantum dots when connected to PdNi electrodes via tunneling barriers is combined with the particular transversal anisotropy of the PdNi when shaped in nanometric stripes.For devices exploiting actively the electronic spin, however control over classical or quantum spin rotations has still to be achieved. A detailed understanding of the magnetic characteristics of PdxNi 100-x alloy is crucial both for understanding the switching characteristics of such the spin-valve device and for optimizing its electronic properties. We present a magnetic study of Pd20Ni80 and Pd90Ni10 nanostripes by means of extraordinary Hall effect measurements, at low temperature, for various dimensions, thicknesses and capping films. In the case of Pd20Ni80, this experiment is a first at low temperature.The CNT-based device proposed here was tested both in linear and nonlinear transportregimes. While the linear spin dependent transport displays the usual signatures of electronicconfinement, the finite bias magnetoresistance displays an impressive magnetoresistance antisymmetric reversal in contrast with the linear regime. This effect can only be understood if electronic interactions are considered. It is accompanied by a linear dispersion of the zeromagnetoresistance point in the bias-field plane. Simulations based on a proposed model confirm a current induced spin precession, electrically tunable due to the quantum nature ofthe device.

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5

LUCCI, MASSIMILIANO. "Gas sensor based on single wall carbon nanotubes." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2008. http://hdl.handle.net/2108/601.

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Single-walled carbon nanotubes (SWNTs) are nowadays one of the most investigated materials and the realization of ordered SWNT structures is of fundamental importance for the improvement of many technological fields, from the non-linear optics to the realization of transistor, to the assembly of gas sensing devices. A SWNT is formed by rolling a graphene sheet into a seamless cylinder with a diameter on the nanometer scale. The individual SWNTs are joined each other and assembled into bundles by Van der Waals forces. Guest molecules can potentially interact with SWNTs via the outer surfaces of bundles, the inside of the tubes and /or the interstitial channels between the tubes in a bundle. These different situations are expected to play an important role in tuning the guest molecule/SWNT interaction during gas adsorption and/or desorption, and have been investigated theoretically and experimentally using different approaches. In particular, the interaction between gaseous molecules and SWNTs has been investigated from different point of view, including gas storage and gas detection through modification of electronic and thermal properties or through modification of the field emission properties. Compared with conventional solid-state sensors, that typically operate at temperatures over 200 °C, and conducting polymers-based sensors, that provide only limited sensitivity, sensing devices assembled with single-wall nanotubes can exhibit high sensitivity and fast response time at room temperature. Due to the high surface area of nanotubes, a little amount of nanotube material can provide many sites for gas interaction. The accessibility of these sites depends on the status of aggregation of the nanotubes. Our preliminary studies suggested that the sensitivity of a nanotube-based device can be optimized controlling the organization of the SWNTs. Ordered bundles of SWNTs exhibit indeed a sensitivity double with respect to that of a disordered deposit. This is likely due to the enhancement of surface area for organized SWNT systems with respect to randomly placed SWNT bundles. Hence, aligned nanotubes can serve as a very efficient material for use in gas detection. Directionality of SWNT can be obtained directly during the synthesis process, or after manipulation of dispersed nanotubes, by mean of several methods, such as filtration/deposition from suspension in strong magnetic fields, field emission, electrophoresis or dielectrophoretical processes. In particular the use of electric fields to move, position and align SWNTs has been reported in recent papers and the results indicate that both the electrophoresis (EP) and dielectrophoresis (DEP) routes have potential advantages for arranging nanotubes in controlled systems. Beyond the sensitivity, another severe constraint for gas detection is the time either for the reset of the sensor after exposure to the gas, either for the acceleration of the response itself. Since practical applications can be severely limited by slow absorption/desorption processes, we felt it worthwhile to investigate in a systematic way some physical parameters affecting the sensor response. In this thesis we present a study of NH3 ,NOx and H2 detection using organized SWNTs as sensing material and an innovative procedure to improve the time response of the sensor by applying a back gate voltage. Moreover study on gas detection and gas storage were done using QCM sensor.

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6

Liang, Jianghong. "Single Wall Carbon Nanotube/Polyacrylonitrile Composite Fiber." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7613.

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Single Wall Carbon Nanotubes (SWNTs), discovered in 1993, have good mechanical, electrical and thermal properties. Polyacrylonitrile (PAN) is an important fiber for textiles as well as a precursor for carbon fibers. PAN has been produced since 1930s. In this study, we have processed SWNT/PAN fibers by dry-jet wet spinning. Purified SWNT, nitric acid treated SWNTs, and benzonitrile functionalized SWNTs have been used. Fiber processing was done in Dimethyl Formamide (DMF) and coagulation was done in DMF/water mixture. The coagulated fibers were drawn (draw ratio of 6) at 95 oC. Structure, orientation, and mechanical properties of these fibers have been studied. The cross-sections for all the fibers are not circular. Incorporation of SWNT in PAN results in improved mechanical properties, tensile modulus increased from 7.9 GPa for control PAN to 13.7 GPa for SWNT/PAN composite fiber, and functionalized SWNTs result in higher improvements with tensile modulus reaching 17.8 GPa for acid treated SWNT/PAN composite fibers. The theoretical analysis suggests that observed moduli of the composite fibers are consistent with the predicted values.

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7

Yang, Yang. "Electronic devices based on individual single wall carbon nanotubes." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708116.

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8

Gao, Bo. "Multi-terminal elecron transport in single-wall carbon nanotubes." Paris 6, 2006. http://www.theses.fr/2006PA066176.

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9

Wang, Tong. "Light Scattering Study on Single Wall Carbon Nanotube (SWNT) Dispersions." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5200.

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Carbon nanotubes, and particularly single wall carbon nanotubes (SWNTs) have attracted much attention for their unique structure, as well as for their excellent mechanical, electrical and thermal properties. Most properties of carbon nanotubs are closely related with its anisotropic structure and geometry factor. Characterization of carbon nanotube length is critical for understanding their behavior in solutions as well as in polymer composites. Microscopy, particularly atomic force microscopy, has been used for their length measurement. Microscopy, though straightforward, is quite laborious, particularly for statistically meaningful sampling. Light scattering can be used to measure particle dimensions. In this study, light scattering has been used to study polyvinyl pyrrolidone (PVP) wrapped SWNTs surfactant assisted aqueous dispersion and SWNT dispersion in oleum. To determine the length of SWNTs, Stokes - Mueller formalism was used, which is a universal model for particles with any size and shape. The Mueller matrix for an ensemble of long, thin cylinders proposed by McClain et al. was used in this study. This Mueller matrix includes the information of size (length and radius) and optical constants (refractive index and extinction coefficient) of cylinders. In this matrix, extinction coefficient, radius and length of SWNTs are unknown. By normalizing scattering intensity I(theta) (theta from 30 to 155 degree) to that at 30degree , the effects of radius and extinction coefficient were cancelled out. Thus, the effect of SWNT length on scattering intensity could be studied independently. A series of curves of normalized scattering intensity of SWNTs (I(theta) /I(30degree)) with varied length as a function of wave vector were predicted. A curve of normalized scattering intensity of SWNT as a function of wave vector was also obtained experimentally. By comparing experimental and predicted curves, average SWNT length in the dispersion has been determined. Scattering intensity at a given angle initially increases with concentration, and then reaches a critical concentration(C*), above which the scattering intensity decreases. This phenomenon has been attributed to the competition between scattering and absorption of light by the presence of SWNT. By using Beer-Lambert law, this phenomenon has been used to determine the molar absorption coefficient of SWNTs.

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10

Liu, Huijun. "Properties of small radius single-wall carbon nanotubes from first-principles calculations /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202003%20LIU.

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11

Rabiu, Aminu. "Adsorption of single-wall carbon nanotubes at liquid/liquid interface." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/adsorption-of-singlewall-carbon-nanotubes-at-liquidliquid-interface(ffd86c99-bcf7-46e4-b159-a89c77e850fa).html.

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In this thesis, the adsorption of single-wall carbon nanotubes (SWCNTs) at the liquid/liquid interface, and the subsequent electrochemical investigation of the electrical properties of the adsorbed nanotubes have been studied. Prior to the adsorption of the nanotube, the stability of dispersion of SWCNTs in non-aqueous solvents was assessed by determining the onset of aggregation of the SWCNTs when organic electrolyte was introduced. It was found that electrostatic repulsion between the SWCNTs contributes significantly to the stability of the SWCNTs in non-aqueous solvents. Similar result was also found when the aggregation kinetics of molybdenum disulphide (MoS2) dispersion in non-aqueous media was studied using the same organic electrolyte. The formation of nanomaterial-polymer composites by deliberate electrochemical oxidation of pyrrole and the sonochemical polymerisation of the organic solvent was also studied. Electrolyte addition was shown to be a promising way to separate the 2D material from the sonopolymer.

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12

Xhyliu, Fjorela. "Surface Functionalization and Optical Spectroscopy of Single-wall Carbon Nanotubes." Cleveland State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=csu1599143727075125.

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13

Malard, L. M., D. Nishide, L. G. Dias, Rodrigo B. Capaz, A. P. Gomes, A. Jorio, C. A. Achete, et al. "Resonance Raman study of polyynes encapsulated in single-wall carbon nanotubes." American Physical Society, 2007. http://hdl.handle.net/2237/11303.

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14

Teh, Aun Shih. "In-situ synthesis of single wall carbon nanotubes for electronic devices." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612322.

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15

Kishida, Hideo, Yoshiaki Nagasawa, Sadanobu Imamura, and Arao Nakamura. "Direct Observation of Dark Excitons in Micelle-Wrapped Single-Wall Carbon Nanotubes." American Physical Society, 2008. http://hdl.handle.net/2237/11298.

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16

MENDONZA, CESAR AUGUSTO DIAZ. "PHOSPHORUS INCORPORATION IN SINGLE WALL CARBON NANOTUBES PRODUCED BY HIGH VACUUM CVD." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24237@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Neste trabalho estudamos a síntese e caracterização de nanotubos de carbono de paredes simples com incorporação de fósforo. Os nanotubos foram produzidos em duas diferentes temperaturas (800 e 850 Graus Celsius), usando um precursor em pó (fase sólida) sem diluição em nenhum liquido. O sistema utilizado na síntese foi o CVD em alto vácuo. Para a caracterização comparamos as amostras incorporadas com SWNTs crescidos com etanol. Usamos a espectroscopia Raman, espectroscopia de fotoelétrons induzida por raios x (XPS) e microscopia eletrônica de transmissão (TEM) para caracterizar as amostras. A espectroscopia Raman e a microscopia eletrônica de transmissão foram usadas para confirmar a presença de SWNTs na amostra. Encontramos evidencia de que o fósforo foi incorporado nas amostras ao compararmos os espectros Raman dos SWNTs com amostra de referência. A partir dos resultados de XPS, observamos a presença de fósforo ligado a átomos de carbono que nós faz concluir que houve incorporação de fósforo nos nanotubos.
In this work was studied the synthesis and characterization of single wall carbon nanotubes (SWCN) with phosphorus incorporation. The nanotubes were produced in two different temperatures (800 and 850 Degrees Celsius), using a powder precursor (solid phase) without liquid dilution. The system used for the synthesis was High Vacuum Chemical Vapor Deposition (HVCVD). The samples were characterized comparing the samples with phosphorus with SWNT synthetized with ethanol. Raman spectroscopy, x-ray photoelectron spectroscopy (XPS) on transmission electron microscopy (TEM) were employed to characterize the samples. The Raman spectroscopy and TEM were employed to confirm the presence of SWNT in the samples. We found evidences that phosphorus were incorporated comparing the Raman spectra with the reference sample. The XPS results showed the presence of phosphorus atoms bonded to carbon atoms which make us conclude that the phosphorus were incorporated to the nanotubes.

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17

Bair, Shawn D. "Computational Modeling of the Electrical Sensing Properties of Single Wall Carbon Nanotubes." Youngstown State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1441813278.

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18

Liu, Shuhan Jr. "Single wall carbon nanotube based nanoparticles and hydrogel for cancer therapy." Journal of Materials Chemistry B, 2014. http://hdl.handle.net/1993/23149.

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Nowadays, cancer treatment and tissue regeneration have attracted large amount of attention. Single Wall Carbon Nanotubes (SWNT) possess large surface area and outstanding optical and electrical performance, making it a promising component in cancer therapy and tissue reengineering systems. In this study, four disease treating systems based on SWNT are developed. They are pH-sensitive poly(ethylene glycol)-doxorubicin(PEG-DOX)@SWNT drug release system, temperature sensitive SWNT hydrogel, SWNT based biocompatible magnetic hydrogel and biocompatible SWNT-gelatin-F127-cysteamine hydrogel for tissue engineering. The successfully synthesized target compounds are characterized by FTIR. The in vitro release of drugs from the drug release systems is evaluated upon changes of pH values and the laser scanning. The effect of cancer treatment systems on specific kind of cells are examined by confocal laser scanning microscopy (CLSM). The results indicate that all of the four systems show great potential in the biomedical applications especially in disease therapy applications.

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19

Jackson, Roderick Kinte'. "Development of single wall carbon nanotube transparent conductive electrodes for organic electronics." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29635.

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Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Graham, Samuel; Committee Member: Garimella, Srinivas; Committee Member: Kippelen, Bernard; Committee Member: Melkote, Shreyes; Committee Member: Ready, Jud. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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20

GALIMBERTI, GIANLUCA. "TIME RESOLVED OPTICAL MEASUREMENTS ON DIFFERENT CARBON NANOTUBES ARCHITECTURES." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/168735.

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Multi Wall Carbon Nanotubes (MWCNT) and Single Wall Carbon Nanotubes (SWCNT) can be grown in several architectures. A crucial aim is the theoretical and experimental study of the fundamental dynamics of photo-excited charge carriers into these ensembles. In fact the understanding of the charge transfer dynamics and of the exciton interaction is of great importance to improve the efficiency of the Carbon Nanotubes (CNT) based applications, as sensor, bio-medical, energy storage and photovoltaic technologies. In this thesis, performing time resolved optical measurements with several experimental techniques, we analyze the fundamental dynamics in different CNT architectures. Charge transfer mechanisms from semiconductor to metallic are evidenced in unaligned SWCNT, whereas this process is not present in the vertically aligned. The excitonic behavior, revealed in all ensembles, are an interesting novelty in aligned MWCNT. The study of this behavior allows to addressed a long debated question about the graphite-like or SWCNT-like behavior of MWCNT, unveiling that the MWCNT electronic structure under 3 eV presents structured peaks like the Van Hove Singularities in SWCNT. Non-linear excitonic effects are analyzed and, controlling the light polarization direction with respect to the CNT long-axis, we are able to select and unveil, in MWCNT architectures, different optical responses, evidencing linear and non-linear effects. In particular exciton-exciton annihilation and Multiple Exciton Generation (MEG) non-linear processes are discussed. The initial studies on a possible presence of MEG in MWCNT can pave the way to disentangle the complex processes occurring in the photo-excited MWCNT in the violet light region. The possibility to control the effects as a multiple generation of excitons represent crucial challenges in order to improve the photovoltaic performances of MWCNT based devices. This thesis represents the initial step of a wide project whose ultimate goal is to improve the efficiency of photovoltaic devices based on SWCNT or MWCNT. In order to address this aim, heterogeneous systems are considered, in which different CNT architectures are combined with nanoparticles or organic groups. Starting from the basic systems and adding in subsequent stages the different components up to the complete devices, for each step the optical response will be studied.

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21

Torres, Dias Abraao Cefas. "Effects of high pressure on empty and water-filled single-wall carbon nanotubes studied by Raman spectroscopy." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10283/document.

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La présente thèse est constituée par un ensemble d'études expérimentales sur l'effet des hautes pressions sur les nanotubes de carbone mono-parois, individualisées, fermés ou ouvertes, donc vides ou remplis d'eau. Les techniques des hautes pressions et de la spectroscopie Raman ont été combinées afin d'étudier l'effondrement des nanotubes et de sonder les modifications induites par l'effet de la pression. Les coefficients de pression des modes radiaux de respiration (RBM) ont été obtenus avec identification individuelle par chiralité. Les RBM des nanotubes remplis d'eau ont pu être observés à des pressions bien plus élevées que pour des nanotubes vides. Après un cycle à haute pression, les nanotubes vides de diamètre plus important n'étaient pas détectables tandis que les tubes de diamètre sous-nanométrique se sont remplis d'eau. Ces observations suggèrent que les nanotubes de diamètre le plus faible ont une meilleur stabilité sous pression qui est accrue par le remplissage par de l'eau. Une réponse inusuelle du nanotube (7,2) suggère que la chiralité peut avoir aussi un rôle aussi important dans la stabilité structurelle, en tout cas pour les nanotubes de plus faibles diamètres. De son côté, l'évolution des modes de vibration tangentiels suggère l'effondrement radial des nanotubes vides d'un diamètre d'environ de 1.32 nm à une pression proche de 4 GPa, en accord avec les prévisions théoriques les plus récentes. Ces mêmes tubes remplis d'eau, présentent un effondrement à une pression qui se situe au-delà de 16 GPa
The present thesis constitutes a set of experimental studies on the effect of high pressures on single wall carbon nanotubes, individualized, closed or open, therefore empty or filled with water. High-pressure techniques and Raman spectroscopy were combined to study the radial collapse, as well to probe the pressure-induced modifications. Chirality-resolved pressure derivatives were obtained for the radial breathing modes (RBM). The RBM of water-filled could be observed at pressures higher than those of empty. After a high-pressure cycle, empty nanotubes of larger diameters were not detectable anymore, while sub nanometric diameter ones became filled with water. Such observations suggest that thinner nanotubes have better pressure-stability, which is increased upon water filling. An unusual response of the (7,2) nanotube suggests that the chirality may have also an important role on the structural stability for small diameters. The evolution of the tangential modes suggest the onset of radial collapse of empty nanotubes averaging 1.32 nm diameter at about 4 GPa, in agreement with the latest theoretical predictions. These same nanotubes, though water-filled, they collapse at pressures higher than 16 GPa

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Ibrahim, Imad. "Fabrication of high yield horizontally aligned single wall carbon nanotubes for molecular electronics." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-117433.

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The extraordinary properties of the single wall carbon nanotubes (SWCNTs) have stimulated an enormous amount of research towards the realization of SWCNT-based products for different applications ranging form nanocomposites to nanoelectronics. Their high charge mobility, exceedingly good current-carrying capacities and ability to be either semiconducting or metallic render them ideal building blocks for nanoelectronics. For nanoelectronic applications, either individual or parallel aligned SWCNTs are advantageous. Moreover, closely packed arrays of parallel SWCNTs are required in order to sustain the relatively large currents found in high frequency devices. Two key areas still require further development before the realization of large-scale nanoelectronics. They are the reproducible control of the nanotubes spatial position/orientation and chiral management. In terms of nanotube orientation, different techniques have been demonstrated for the fabrication of horizontally aligned SWCNTs with either post synthesis routes (e.g. dielectrophoresis and Langmuir-Blodgett approach) or direct growth (e.g. chemical vapor deposition (CVD)). The low temperature of the production process, allowing the formation of aligned nanotubes on pretty much any substrate, is the main advantage of the post synthesis routes, while the poor levels of reproducibility and spatial control, and the limited quality of the aligned tubes due to the inherently required process steps are limitations. The simplicity, up-scalability, along with the reproducible growth of clean high quality SWCNTs with well-controlled spatial, orientation and length, make CVD the most promising for producing dense horizontally well-aligned SWCNTs. These CVD techniques suffer some drawbacks, namely, that because they are synthesized using catalyst particles (metals or non-metals) the catalyst material can contaminate the tubes and affect their intrinsic properties. Thus, the catalyst-free synthesis of aligned SWNT is very desirable. This thesis comprises detailed and systematic experimental investigations in to the fabrication of horizontally aligned SWCNTs using both post growth (Dielectrophoresis) and direct growth (CVD) methods. Both catalyst-assisted and catalyst-free SWCNTs are synthesized by CVD. While metallic nanoparticles nucleate and grow SWCNTs, opened and activated fullerene structures are used for all carbon catalyst-free growth of single wall and double wall carbon nanotubes. The systematic studies allow for a detailed understanding of the growth mechanisms of catalyst and catalyst-free grown SWCNTs to be elucidated. The data significantly advances our understanding of horizontally aligned carbon nanotubes by both post synthesis alignment as well as directly as-synthesized routes. Indeed, the knowledge enables such tubes to be grown in high yield and with a high degree of special control. It is shown, for the first time, how one can grow horizontally aligned carbon nanotubes in crossbar configurations in a single step and with bespoke crossing angles. In addition, the transport properties of the aligned tubes at room temperature are also investigated through the fabrication of devices based on these tubes
Die außergewöhnlichen Eigenschaften von einwandigen Kohlenstoffnanoröhren (engl. single wall carbon nanotubes, SWCNTs) haben bemerkenswerte Forschungsaktivitäten zur Verwirklichung von auf SWCNTs basierenden Anwendungen für verschiedene Bereiche, die von Nanokompositen bis hin zur Nanoelektronik reichen, stimuliert. Ihre hohe Ladungsträgermobilität und die außerordentlichen hohen Ladungsdichten, die in SWCNTs erreicht werden können sowie ihre Eigenschaft, entweder halbleitend oder metallisch zu sein, machen sie zu idealen Konstituenten von nanoelektronischen Schaltkreisen. Für Anwendungen in der Nanoelektronik sind entweder einzelne oder parallel angeordnete SWCNTs vorteilhaft. Darüber hinaus sind dicht gepackte Anordnungen von SWCNTs erforderlich, um die relativ hohen Ströme in Hochfrequenzbauelementen zu transportieren. Für eine erfolgreiche Realisierung von großskaligen nanoelektronischen Bauteilen, die auf SWCNTs basieren, sind noch zwei enorm wichtige Kernprobleme zu lösen, die weitere Forschungsanstrengungen erfordern: die reproduzierbare und verlässliche Kontrolle der räumlichen Positionierung und Orientierung der Nanoröhren sowie die Kontrolle der Chiralität der einzelnen SWCNTs. Hinsichtlich der Orientierung der Nanoröhren kann die horizontal parallele Ausrichtung von SWCNTs mit verschiedenen Techniken erreicht werden. Diese setzen entweder nach dem eigentlichen Wachstum der Röhren ein (Post-Synthese-Methoden wie z.B. Dielektrophorese oder Langmuir-Blodgett-Techniken) oder erreichen direkt während des Wachstums (z.B. durch Chemical-Vapor-Deposition-Methoden (CVD)) die parallele Anordnung. Durch die niedrigen Prozesstemperaturen, die während des Herstellungsprozesses erforderlich sind, erlauben die nach der eigentlichen Synthese stattfindenden Ausrichtungsmethoden die parallele Anordnung von Nanoröhren auf nahezu jedem Substrat, jedoch stellen die geringe Reproduzierbarkeit dieser Prozesse, die schwierige Kontrollierbarkeit der räumlichen Anordnung und die limitierte Qualität der ausgerichteten Röhren aufgrund der erforderlichen Prozessschritte natürliche Beschränkungen dieser Techniken dar. Die einfache Durchführung und ihre Skalierbarkeit, zusammen mit dem reproduzierbaren Wachstum qualitativ sehr hochwertiger SWCNTs mit hoher Kontrolle von räumlicher Anordnung, Orientierung und Länge machen die CVD-Methode zur erfolgversprechendsten Technik für die Herstellung von dichtgepackten hochparallelen horizontalen Anordnungen von SWCNTs. Diese CVD-Ansätze weisen jedoch auch einige Nachteile auf, die in den bei der Synthese verwendeten Katalysatorpartikeln (metallisch oder nicht-metallisch) begründet liegen, da das Katalysatormaterial die Röhren kontaminieren und dadurch ihre intrinsischen Eigenschaften beeinflussen kann. Daher ist eine katalysatorfreie Synthesemethode für ausgerichtete SWCNTs ein höchst erstrebenswertes Ziel. Die vorliegende Arbeit beschreibt detaillierte und systematische experimentelle Untersuchungen zur Herstellung von horizontalen, parallel ausgerichteten Anordnungen von SWCNTs unter Verwendung von Methoden, die sowohl nach dem eigentlichen Wachstum der Nanoröhren (Dielektrophorese) als auch während des Wachstums ansetzen (CVD). Bei den CVD-Methoden werden sowohl solche, die auf der Verwendung von Katalysatoren basieren, als auch katalysatorfreie Techniken verwendet. Während metallische Nanopartikel den Ausgangspunkt für das Wachstum von SWCNTs darstellen, werden geöffnete und aktivierte Fullerenstrukturen verwendet, um das katalysatorfreie Wachstum von reinen ein- oder mehrwandigen Nanoröhren zu erreichen. Die systematischen Untersuchungen ermöglichen ein tiefgehendes Verständnis der Wachstumsmechanismen von SWCNTs, die unter Verwendung von Katalysatoren oder katalysatorfrei erzeugt synthetisiert wurden. Die erzielten Ergebnisse erhöhen in einem hohen Maß das Verständnis der Herstellung von horizontal parallel angeordneten Nanoröhren, die durch Post-Synthese-Methoden oder direkt während des Wachstumsprozesses ausgerichtet wurden. Die erzielten Einsichten erlauben die Herstellung solcher Strukturen mit hoher Ausbeute und mit einem hohen Maß an räumlicher Kontrolle der Anordnung. Zum ersten Male kann ein Verfahren präsentiert werden, mit dem horizontal parallel angeordnete Nanoröhren in gekreuzten Strukturen mit wohldefinierten Kreuzungswinkeln hergestellt werden können. Zusätzlich werden die Transporteigenschaften von parallel ausgerichteten Nanoröhren bei Raumtemperatur, durch die Herstellung von auf den dargestellten Strukturen basierenden Bauelementen, untersucht

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23

Ecton, Philip. "Low-Energy Electron Irradiation of Preheated and Gas-Exposed Single-Wall Carbon Nanotubes." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc955114/.

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We investigate the conditions under which electron irradiation of single-walled carbon nanotube (SWCNT) bundles with 2 keV electrons produces an increase in the Raman D peak. We find that an increase in the D peak does not occur when SWCNTs are preheated in situ at 600 C for 1 h in ultrahigh vacuum (UHV) before irradiation is performed. Exposing SWCNTs to air or other gases after preheating in UHV and before irradiation results in an increase in the D peak. Small diameter SWCNTs that are not preheated or preheated and exposed to air show a significant increase in the D and G bands after irradiation. X-ray photoelectron spectroscopy shows no chemical shifts in the C1s peak of SWCNTs that have been irradiated versus SWCNTs that have not been irradiated, suggesting that the increase in the D peak is not due to chemisorption of adsorbates on the nanotubes.

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Al, abboodi Mohammed Halool. "ELECTRONIC AND VIBRATIONAL PROPERTIES OF SINGLE WALL CARBON NANOTUBES AND BORON NITRIDE NANOTUBES IN THE PRESENCE OF VARIOUS IMPURITIES." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1672.

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The major objective of this thesis is to systematically investigate the effect of hexagonal BN (h-BN) islands on electronic and vibrational properties of single wall carbon Nanotubes. All our investigation are based on first principle Density Functional Theory (DFT) calculations. Our study is motivated by interesting metal-semiconductor transition recently found in periodically patterned graphene with h-BN islands. After reproducing the electronic band structure for pristine single wall zigzag carbon nanotubes (which shows metallic or semiconducting properties depending on their chirality), we investigated their electronic band structure in the presence of h-BN islands. The band structure depends not only on the defect concentration, but also on the pattern of the defect atoms. Our results also suggest that, if we start with a metallic /semiconducting mixture of ZSWCNTs, upon h-BN addition, the sample converts to fully semiconducting. This is a promising result for applications of CNTs in molecular electronics. Fundamental understanding of vibrational properties of nano electronics component is equally important in their applications especially in thermal management and thermoelectric applications. Defect engineering is one of the potential approach for tuning nanoelectronic devices for optimal thermal management and thermoelectric devices. In this work, I present a systematic investigation on how the group velocity and frequency of different phonon modes depend on various h-BN defect concentrations and defect patterns in ZSWCNTs. The study was extended to investigate the effect of hexagonal-C defects on the electronic and vibrational properties of zigzag single wall Boron Nitride nanotubes (ZSWBNNTs).

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Sugai, Toshiki, Hideki Omote, Shunji Bandow, Nobuo Tanaka, and Hisanori Shinohara. "Production of fullerenes and single-wall carbon nanotubes by high-temperature pulsed arc discharge." American Institute of Physics, 2000. http://hdl.handle.net/2237/7058.

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26

Lee, Kuen-Chan. "New strategies for non-covalent chemical functionalisation and dispersion of single-wall carbon nanotubes." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526495.

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MONTEIRO, FERNANDO HENRIQUE DO REGO. "A STUDY ON THE PRODUCTION AND CHARACTERIZATION OF BORON DOPED SINGLE WALL CARBON NANOTUBES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=35271@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
BOLSA NOTA 10
Neste trabalho estudamos a síntese e caracterização de nanotubos de carbono de parede simples dopados com boro, que foram produzidos em diferentes condições, usando um precursor líquido em um sistema CVD de alto vácuo. Para a caracterização comparamos as amostras com outras − de referência sem dopagem − e também usamos microscópios de transmissão e varredura, espectroscopia Raman e espectroscopia por fotoelétrons excitados por raio X (XPS). A microscopia de transmissão e a espectroscopia Raman foram usadas para confirmar a presença de nanotubos de parede simples, enquanto a microscopia de varredura foi usada para identificar em qual faixa de temperatura os nanotubos foram produzidos. Achamos evidências de que as amostras estão dopadas ao compararmos os espectros Raman dos nanotubos com as amostras de referência. Usando os resultados do XPS, determinamos que os nossos tubos estão dopados com boro. Comparando a análise Raman com esses resultados, desenvolvemos uma regra simples para estimar o nível de dopagem a partir de medidas Raman.
We studied in this work the synthesis and characterization of boron doped single wall carbon nanotubes. They were produced, at different conditions, using a new liquid precursor in a high vacuum chemical vapour deposition system. In order to characterize the samples we compared them to an undoped reference sample and used a transmission and field emission scanning electron microscopy, Raman spectroscopy and a X-ray photoemission spectroscopy (XPS). The transmission electron microscopy and the Raman spectroscopy were used to confirm the presence of single wall carbon nanotubes, while the scanning electron microscopy was used to identify in which temperature range the tubes were produced. We found evidences that the produced sample were doped by comparing the Raman spectra of the samples with the reference one. By using the XPS, we could determine that our tubes are boron doped. By comparing the Raman analysis with the XPS results, we developed a simple rule to estimate the doping level through Raman measurements.

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Al, Mafarage Ali M. "Processing and Properties of Multifunctional Two-Dimensional Nanocomposite Based on Single Wall Carbon Nanotubes." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1556310855748631.

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DiLillo, Ana M. ""Noncovalent Complexation of Single-Wall Carbon Nanotubes with Biopolymers: Dispersion, Purification, and Protein Interactions"." Cleveland State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=csu1624461866858216.

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Eberhardt, Oliver, and Thomas Wallmersperger. "Molecular mechanics methods for individual carbon nanotubes and nanotube assemblies." SPIE, 2015. https://tud.qucosa.de/id/qucosa%3A35032.

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Since many years, carbon nanotubes (CNTs) have been considered for a wide range of applications due to their outstanding mechanical properties. CNTs are tubular structures, showing a graphene like hexagonal lattice. Our interest in the calculation of the mechanical properties is motivated by several applications which demand the knowledge of the material behavior. One application in which the knowledge of the material behavior is vital is the CNT based fiber. Due to the excellent stiffness and strength of the individual CNTs, these fibers are expected to be a promising successor for state of the art carbon fibers. However, the mechanical properties of the fibers fall back behind the properties of individual CNTs. It is assumed that this gap in the properties is a result of the van-der-Waals interactions of the individual CNTs within the fiber. In order to understand the mechanical behavior of the fibers we apply a molecular mechanics approach. The mechanical properties of the individual CNTs are investigated by using a modified structural molecular mechanics approach. This is done by calculating the properties of a truss-beam element framework representing the CNT with the help of a chemical force field. Furthermore, we also investigate the interactions of CNTs arranged in basic CNT assemblies, mimicking the ones in a simple CNT fiber. We consider the van-der-Waals interactions in the structure and calculate the potential surface of the CNT assemblies.

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Anto, Thomas Bibin [Verfasser]. "Single wall carbon nanotubes based transparent conducting films for flexible electronics applications / Thomas Bibin Anto." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1068333138/34.

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Khanal, Rajendra R. "Carbon Single Wall Nanotubes: Low Barrier, Cu- Free Back Contact to CdTe Based Solar Cells." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1396625969.

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33

Valasma, R. (Ronja). "Micropatterned transparent conductive films of single-wall carbon nanotubes on plasma-treated polyethylene terephtalate surfaces." Bachelor's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201906042332.

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Abstract. Flexible transparent conductive films of micropatterned carbon nanotube networks are studied in this thesis. Plasma etching through a contact mask was used to form hydrophilic micropatterns on the surface of polyethylene terephthalate foils, which enabled the selective deposition of single-wall carbon nanotubes from their aqueous dispersions by simple dip-coating. A higher density grid-type pattern was used in conjunction with a highly concentrated ink to create transparent conductive films with sheet resistances below 10 kΩ/◻️ on the mechanically flexible polymer, which was then found suitable for capacitive touch screen applications. To confirm the conduction process in the films is due to the percolation, also a lower density line pattern was made and coated using a dispersion of lower concentration.Yksiseinäisistä hiilinanoputkista valmistetut mikrokuvioidut läpinäkyvät johtavat kalvot plasma käsitellyllä polyetyleenitereftalaatti pinnalla. Tiivistelmä. Tämän kandintyön tutkimuskohde on mikrokuvioiduista hiilinanoputkiverkostoista koostuvat läpinäkyvät johtavat kalvot (transparent conductive film, TCF). Hydrofiilisen mikrokuvion muodostamiseen polyetyleenitereftalaattikalvon pinnalle käytettiin plasmaetsausta, mikä mahdollisti selektiivisen hiilinanoputkien päällystyksen vesipohjaisista dispersioista yksinkertaisella kastamismenetelmällä. Tiiviimpi ristikkomainen kuvio käytettynä korkeamman pitoisuuden dispersion kanssa sai aikaa kalvoja, joiden pintavastus oli parhaimmillaan alle 10 kΩ/◻ mekaanisesti taipuisan polymeerin päällä. Tällaisen kalvon todettiin olevan sopiva kapasitiivisiin kosketusnäyttösovelluksiin. Jotta johtavuus kalvoissa voitaisiin liittää perkolaatioon, tehtiin myös kalvoja harvemmalla viivakuviolla käyttäen matalamman pitoisuuden dispersiota.

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34

Gupta, Ankit. "Multi-Scale Modeling of Mechanical Properties of Single Wall Carbon Nanotube (SWCNT) Networks." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1022.

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Single wall carbon nanotubes (SWCNTs) show a variety of unparalleled properties such as high electrical and thermal conductivity, high specific surface area (SSA) and a large stiffness under axial loads. One of the major challenges in tapping the vast potential of SWCNTs is to fabricate nanotube based macrostructures that retain the unique properties of nanotubes. Pristine SWCNT aerogels are highly porous, isotropic structures of nanotubes mediated via van der Waals (VDW) interactions at junctions. The mechanical behavior of such aerogels is examined in several experimental studies. However, it is necessary to supplement these studies with insights from simulations in order to develop a fundamental understanding of deformation behavior of SWCNT aerogels. In this study, the mechanical behavior of SWCNT networks is studied using a multi-scale modeling approach. The mechanics of an individual nanotube and interactions between few nanotubes are modeled using molecular dynamics (MD) simulations. The results from atomistic simulations are used to inform meso-scale and continuum scale finite element (FE) models. The deformation mechanism of pristine SWCNT networks under large compressive strain is deduced from insights offered by meso-scale simulations. It is found that the elasticity of such networks is governed by the bending deformation of nanotubes while the plastic deformation is governed by the VDW interactions between nanotubes. The stress response of the material in the elastic regime is dictated by the VDW stresses on nanotubes while in the plastic regime, both the VDW and axial deformation stresses on nanotubes drive the overall stress response. In this study, the elastic behavior of a random SWCNT network with any set of junction stiffness and network density is also investigated using FE simulations. It is found that the elastic deformation of such networks can be governed either by the deformation of the nanotubes (bending, axial compression) or deformation of the junctions. The junction stiffness and the network density determine the network deformation mode. The results of the FE study are also applicable to any stiff fiber network.

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35

Jayasinghe, Chaminda. "Functionalization of single wall carbon nanotubes using RF-plasma the role of defects in sidewall functionalization /." Cincinnati, Ohio : University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1185999248.

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Thesis (M.S.)--University of Cincinnati, 2007.
Title from electronic thesis title page (viewed Oct. 8, 2007). Includes abstract. Keywords: SWNTs defects, plasma functionalization, TEP measurements, CNT sidewall functionalization. Includes bibliographical references.

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36

Gaaß, Markus [Verfasser], and Christoph [Akademischer Betreuer] Strunk. "The Kondo effect in single wall carbon nanotubes with ferromagnetic contacts / Markus Gaaß. Betreuer: Christoph Strunk." Regensburg : Universitätsbibliothek Regensburg, 2011. http://d-nb.info/1023361760/34.

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37

Oftadeh, M., M. Gholamian, and H. H. Abdallah. "Investigation of Interaction Hydrogen Sulfide with (5,0) and (5,5) Single-Wall Carbon Nanotubes by DFT Method." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35161.

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In the present study the interaction of Hydrogen Sulfide with inside and outside single-wall carbon nanotube of (5,0) and (5,5) was investigated. This study was conducted using DFT at B3LYP/6-31G* level of theory. Computational calculations were performed in the gaseous phase in Gaussian 09. The geometry of all molecules under investigation was determined by optimizing all geometrical variables without any symmetry constraints. The harmonic frequencies were computed from analytical derivatives for all species in order to define the minimum-energy structures. The adsorption energies, the thermodynamic properties, HOMO-LUMO energy gaps and partial charges of the interacting atoms were also studied during two rotation kinds of H2S molecules vertical and horizontal to the main axes of nanotube. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35161

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38

JAYASINGHE, CHAMINDA. "FUNCTIONALIZATION OF SINGLE WALL CARBON NANOTUBES USING RF-PLASMA: THE ROLE OF DEFECTS IN SIDEWALL FUNCTIONALIZATION." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1185999248.

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39

Wadhawan, Atul. "The Effects of Cesium Deposition and Gas Exposure on the Field Emission Properties of Single Wall and Multiwall Carbon Nanotubes." Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3110/.

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The effects of Cs deposition on the field emission (FE) properties of single-walled carbon nanotube (SWNT) bundles were studied. In addition, a comparative study was made on the effects of O2, Ar and H2 gases on the field emission properties of SWNT bundles and multiwall carbon nanotubes (MWNTs). We observed that Cs deposition decreases the turn-on field for FE by a factor of 2.1 - 2.9 and increases the FE current by 6 orders of magnitude. After Cs deposition, the FE current versus voltage (I-V) curves showed non-Fowler-Nordheim behavior at large currents consistent with tunneling from adsorbate states. At lower currents, the ratio of the slope of the FE I-V curves before and after Cs deposition was approximately 2.1. Exposure to N2 does not decrease the FE current, while exposure to O2 decreases the FE current. Our results show that cesiated SWNT bundles have great potential as economical and reliable vacuum electron sources. We find that H2 and Ar gases do not significantly affect the FE properties of SWNTs or MWNTs. O2 temporarily reduces the FE current and increases the turn-on voltage of SWNTs. Full recovery of these properties occurred after operation in UHV. The higher operating voltages in an O2 environment caused a permanent decrease of FE current and increase in turn-on field of MWNTs. The ratios of the slopes before and after O2 exposure were approximately 1.04 and 0.82 for SWNTs and MWNTs, respectively. SWNTs compared to MWNTs would appear to make more economical and reliable vacuum electron sources.

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40

SHINOHARA, Hisanori, Toshiki SUGAI, and Naoki KISHI. "Synthesis of Single- and Double-Wall Carbon Nanotubes by Gas Flow-Modified Catalyst-Supported Chemical Vapor Deposition." Institute of Electronics, Information and Communication Engineers, 2009. http://hdl.handle.net/2237/14982.

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41

Motaung, David Edmond. "Optical emission spectroscopy of laser induced plasmas containing carbon and transitional metals." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8844_1260782486.

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The spectroscopic, SEM and Raman measurements on carbon nanotubes under the exact conditions of which OES analysis were made showed that at
a pressure of 400 Torr and a flow rate of 200 sccm, the quality and quantity of single-walled carbon nanotubes was the highest.

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42

Chen, Zhihong. "Electric field induced transparency modulation in single wall carbon nanotube ultra-thin films and a method to separate metallic and semiconducting nanotubes." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0002404.

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43

Kalbacova, Jana [Verfasser]. "Micro- and tip-enhanced Raman spectroscopy of single-wall carbon nanotubes: from material studies to device applications / Jana Kalbacova." Chemnitz : Technische Universität Chemnitz, 2018. http://d-nb.info/1215909136/34.

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44

Münich, Peter [Verfasser], Dirk [Akademischer Betreuer] Guldi, and Dirk [Gutachter] Guldi. "Novel Photoactive Supramolecular Assemblies of Single Wall Carbon Nanotubes and Molecular Dyes / Peter Münich ; Gutachter: Dirk Guldi ; Betreuer: Dirk Guldi." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1206417161/34.

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45

Maigné, Alan. "Caractérisation et modélisation par microscopie électronique en transmission à balayage (STEM) et spectroscopie de perte d’énergie d’électrons (EELS) de « nanohorns » de carbone monofeuillet fonctionnalisés pour des applications pharmaceutiques Review of recent advances in spectrum imaging and its extension to reciprocal space Revealing the Secret of Water-Assisted Carbon Nanotube Synthesis by Microscopic Observation of the Interaction of Water on the Catalysts Role of Subsurface Diffusion and Ostwald Ripening in Catalyst Formation for Single-Walled Carbon Nanotube Forest Growth Effect of hole size on the incorporation of C60 molecules inside single-wall carbon nanohorns and their release Adsorption Phenomena of Tetracyano-p-quinodimethane on Single-Wall Carbon Nanohorns Carbon Nanohorns as Anticancer Drug Carriers Effect of Functional Groups at Hole Edges on Cisplatin Release from Inside Single-Wall Carbon Nanohorns Optimum Hole-Opening Condition for Cisplatin Incorporation in Single-Wall Carbon Nanohorns and Its Release Functionalization of Carbon Nanohorns with Azomethine Ylides: Towards Solubility Enhancement and Electron-Transfer Processes Aqueous carbon nanohorn–pyrene–porphyrin nanoensembles: Controlling charge-transfer interactions Photoinduced Electron Transfer on Aqueous Carbon Nanohorn–Pyrene– Tetrathiafulvalene Architectures Soluble Functionalized Carbon Nanohorns." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS600.

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La caractérisation et modélisation de « nanohorns » monofeuillets (SWNH) et de forêts de nanotubes par microscopie analytique sont présentées ainsi que leurs applications pour le traitement du cancer. Dans une première partie, nous introduirons les méthodes de microscopie et de spectroscopie utilisées dans nos expériences. Nous étudierons ensuite le processus de croissance de forêts de nanotubes de carbone monofeuillets (dans le contexte d’une collaboration avec l'AIST au Japon). Les SWNH, leur structure, propriétés de remplissage et de fonctionnarisation seront analysés et une nouvelle méthode sera présentée pour l'étude de la porosité de matériaux inorganique en EELS. Des calculs ab-initio seront aussi utilisés pour étudier l'effet des défauts dans les parois des SWNH sur les phénomènes d'oxydation et de remplissage des SWNH. Finalement, nous étudierons les possibles applications de SWNH dans le domaine pharmaceutique, et en particulier pour les traitements cancéreux
In this manuscript, we will expose the characterization and modelling of Single Wall Nanohorns (SWNH) and Nanotube Forests by analytical microscopy and the functionalization of SWNH for drug delivery applications. Firstly, we will introduce the microscopy and spectroscopy methods used for our experiments. We will then study the growth process of Single Wall Carbon Nanotubes (SWCNT) forests (within the framework of a collaboration with AIST, Japan). SWCH, their structure, modifications and filling properties will be analysed in details. An original method will be presented to study the porosity of inorganic material with EELS. Ab initio calculation will also be used to explore the effect of the defects present in the SWNH wall on the oxidation and filling process. We will study the potentialities of Single Wall Carbon nanohorns as Drug Delivery Systems and particularly as anticancer drug carriers

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Pozdnyakov, D. V., A. V. Borzdov, and V. M. Borzdov. "Calculation of Current-Voltage Characteristics of the Optimized Triode with a Cold Cathode Based on the Ordered Array of Single-Wall Metallic Carbon Nanotubes." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35361.

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The current-voltage characteristics of a triode with the plane-parallel electrodes and a cold cathode based on the ordered array of single-wall metallic carbon nanotubes with open ends have been calculated by means of a numerical solution of both the Poisson equation and the quantum-wave equation. The topological parameters of the triode have been optimized. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35361

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Ibrahim, Imad [Verfasser], Gianaurelio [Akademischer Betreuer] Cuniberti, and Stefan E. [Akademischer Betreuer] Schulz. "Fabrication of high yield horizontally aligned single wall carbon nanotubes for molecular electronics / Imad Ibrahim. Gutachter: Gianaurelio Cuniberti ; Stefan E. Schulz." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://d-nb.info/1068444282/34.

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Sun, Anil. "Chemistry of single-wall carbon nanotubes : studies in purification, non-covalent modifîcation by tertiary phosphines and covalent functionalisation via nucleophilic reduction." Thesis, Durham University, 2007. http://etheses.dur.ac.uk/2425/.

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Carbon nanotubes (CNTs) have attracted considerable research interest owing to their exciting properties and potential for a wide range of applications. However, major challenges must be overcome before these applications can be realised. As-prepared CNT material contains a significant proportion of impurities, such as amorphous carbon, fullerenes and metal catalyst particles. The raw CNT material must be purified before the CNTs can be studied and utilised. Also, CNTs tend to aggregate into bundles or "ropes”, and have poor solubility in common solvents, making their handling and processing extremely difficult. Also, many applications require individually separated CNTs. To improve the solubility of CNTs, and amenability to processing on a large scale, chemical modification of CNT surfaces is necessary. To this end, non-covalent as well as covalent strategies have been developed. However, chemical modification may perturb the electronic structure of CNTs, thereby compromising their interesting properties. The challenge, therefore, is to develop chemical modification routes that improve CNT solubility while not seriously affecting their properties. In this work, we firstly study the problem of purification of as-produced CNT material. We have resolved a major controversy concerning the use of oxidising acids for purifying CNTs, which has profound implications for the spectroscopy and subsequent chemical modification of the CNTs. Secondly, we have developed a route for the non- covalent modification of CNTs by tertiary phosphines. This method has the advantages of significantly improving the solubility of CNTs in organic solvents while being extremely simple, not seriously perturbing the CNT electronic structure, as well as not rendering large areas of the CNT inaccessible^ Thirdly, we describe a method for the covalent derivatisation of CNTs based on reduction, followed by electrophilic substitution. This route is considerably more facile and versatile than other covalent functionalisation methods reported to date, and does not cause significant disruption of the CNT electronic structure. Finally, we demonstrate the covalent attachment of formyl (-CHO) groups to CNT walls, which could potentially open the gateway for a plethora of of coupling and modification reactions.

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Poggi, Mark Andrew. "Interfacial and Mechanical Properties of Carbon Nanotubes: A Force Spectroscopy Study." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-09162004-192734/unrestricted/poggi%5Fmark%5Fa%5F200409%5Fphd.pdf.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2005.
Lawrence A. Bottomley, Committee Chair ; F. Levent Degertekin, Committee Member ; Jiri Janata, Committee Member ; Boris Mizaikoff, Committee Member ; Thomas M. Orlando, Committee Member ; Robert L. Whetten, Committee Member. Vita. Includes bibliographical references.

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Forel, Salomé. "Single wall carbon nanotube growth from bimetallic nanoparticles : a parametric study of the synthesis up to potential application in nano-electronics." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX094/document.

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Ce manuscrit présente une étude expérimentale autour de la synthèse des nanotubes de carbone et de leurs possibles intégrations dans des dispositifs. Les remarquables propriétés électroniques et optiques des nanotubes en font un matériau de choix pour entre autres, la nanoélectronique. Néanmoins, l’intégration des nanotubes dans des dispositifs performants est encore aujourd’hui un défi. Cela repose principalement sur la difficulté d’obtenir de grandes quantités de nanotubes mono-paroi avec des propriétés uniformes, propriétés qui sont définies par la structure du nanotube (i.e. leur angle chiral et leur diamètre). Ainsi, réaliser des synthèses de nanotube de carbone avec un contrôle de leur structure représente un point clé pour le progrès dans ce domaine.Nous avons donc mis en place une nouvelle méthode de synthèse de nanotubes de carbone basée sur la chimie de coordination et le dépôt chimique en phase vapeur activé par filament chaud. Cette synthèse permet la conception de nombreux nouveaux catalyseurs bimétalliques pour la croissance des nanotubes de carbone. Comme le procédé mis en place est très générique, des études paramétriques peuvent être réalisées de manière à mieux comprendre l’influence des différents paramètres de la croissance sur la structure des nanotubes obtenue. Nous discuterons ici du rôle de la température et de la composition chimique du catalyseur. Les nanotubes obtenus sont principalement caractérisés par spectroscopie Raman et par microscopies électroniques.Afin de valider les observations obtenues par spectroscopie Raman, les nanotubes synthétisés ont aussi été intégrés dans des dispositifs de type transistor à effet de champ. Une analyse des performances des transistors en fonction des différents nanotubes utilisés dans le canal est présentée.Enfin, les nanotubes intégrés dans ces transistors ont été fonctionnalisés avec un chromophore de ruthénium. Nous avons montré que cette fonctionnalisation nous permet de moduler, grâce à une impulsion lumineuse, la conductivité du dispositif sur trois ordres de grandeur
This manuscript presents an experimental study around the single wall carbon nanotubes (SWCNT) synthesis and their possible integration in nanodevices. The unique electronic and optical properties of carbon nanotubes make them a choice material for various applications, particularly in nano-electronics.Nevertheless, their integration in effective devices is still a challenge. This is mainly due to the difficulty to obtain large quantity of SWCNT with uniform properties, defined by their structure (i.e. chiral angle and diameter). Therefore, structure controlled growth of SWCNTs is a key point for progress in this field.Here, we established a new synthesis approach based on coordination chemistry and hot-filament chemical vapor deposition. This approach allows the design of various bimetallic catalyst nanoparticles for the SWCNT growth. As the synthesis process is generic, parametric study can be performed in order to better understand the influence of the various parameters on the structure of the as-grown SWCNTs. In particular, we will discuss the role of the growth temperature and the chemical composition of the catalyst on the final SWCNTs structure. The obtained SWCNTs are mainly characterized by Raman spectroscopy and electronic microscopy.In order to validate the observations performed by Raman measurement, the synthesized SWCNTs have been also integrated in field effect transistors (FET) devices. An analysis of the performance of the FET-device as a function of the SWCNTs used in its channel will be presented.Finally, SWCNTs integrated in these transistors have been functionalized with an inorganic chromophore of ruthenium.We demonstrate that the functionalization of the SWCNTs leads to a three order of magnitude reversible switch of the device conductivity triggered by visible light

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