Journal articles: 'METALLIC CARBON NANOTUBES'

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Dadashyan L.H., Trofimov R.R., Konobeeva N.N., and Belonenko M.B. "Extremely short pulses in an anisotropic optical medium containing carbon nanotubes with metal conduction." Optics and Spectroscopy 130, no. 12 (2022): 1587. http://dx.doi.org/10.21883/eos.2022.12.55246.49-22.

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In this work, we study the interaction of extremely short pulses with a nonlinear anisotropic optical medium with carbon nanotubes (armchair and zigzag type) with metallic conductivity. The dependence of the pulse shape, width, and intensity on the nanotube chirality indices is analyzed. The most appropriate type of carbon nanotubes is substantiated for providing localized propagation of an electromagnetic field in a medium with anisotropic properties. Keywords: optical anisotropy, extremely short pulse, carbon nanotubes, metallic conduc.

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HIEU, NGUYEN NGOC, and NGUYEN PHAM QUYNH ANH. "ELECTRONIC BAND STRUCTURE OF CARBON NANOTUBES WITH QUINOID STRUCTURE." Modern Physics Letters B 27, no. 25 (September 23, 2013): 1350179. http://dx.doi.org/10.1142/s0217984913501790.

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In this paper, we fully describe the geometry of atomic structure of carbon nanotube with quinoid structure. Electronic energy band structure of carbon nanotubes with quinoid structure is studied by tight-binding approximation. In the presence of bond alternation, calculations show that only armchair (n, n) carbon nanotube (without twisting) remains metallic and zigzag (3ν - 1, -3ν + 1) CNT becomes metallic at the critical elongation. Effect of deformation on the change of band gap is also calculated and discussed.

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Tang, Dai-Ming, Sergey V. Erohin, Dmitry G. Kvashnin, Victor A. Demin, Ovidiu Cretu, Song Jiang, Lili Zhang, et al. "Semiconductor nanochannels in metallic carbon nanotubes by thermomechanical chirality alteration." Science 374, no. 6575 (December 24, 2021): 1616–20. http://dx.doi.org/10.1126/science.abi8884.

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Straining to make a transistor The use of carbon nanotubes (CNTs) as short-channel-length transistors will require control of their chirality, which determines whether they are semiconducting or metallic and if they form strong, low-resistance contacts. Tang et al . fabricated CNT intramolecular transistors by progressive heating and straining of individual CNTs within a transmission electron microscope. Changes to chirality along sections of the nanotube created metallic-to-semiconducting transitions. A semiconducting nanotube channel was covalently bonded to the metallic nanotube source and drain regions. The resulting CNT intramolecular transistors had channel lengths as short as 2.8 nanometers. —PDS

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Lee, Kyu Won, and Cheol Eui Lee. "Half-Metallic Carbon Nanotubes." Advanced Materials 24, no. 15 (March 15, 2012): 2019–23. http://dx.doi.org/10.1002/adma.201200104.

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Khantimerov, S. M., E. F. Kukovitsky, N. A. Sainov, and N. M. Suleimanov. "Fuel Cell Electrodes Based on Carbon Nanotube/Metallic Nanoparticles Hybrids Formed on Porous Stainless Steel Pellets." International Journal of Chemical Engineering 2013 (2013): 1–4. http://dx.doi.org/10.1155/2013/157098.

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The preparation of carbon nanotube/metallic particle hybrids using pressed porous stainless steel pellets as a substrate is described. The catalytic growth of carbon nanotubes was carried out by CVD on a nickel catalyst obtained by impregnation of pellets with a highly dispersive colloidal solution of nickel acetate tetrahydrate in ethanol. Granular polyethylene was used as the carbon source. Metallic particles were deposited by thermal evaporation of Pt and Ag using pellets with grown carbon nanotubes as a base. The use of such composites as fuel cell electrodes is discussed.

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Zhao, Dong Lin, Xia Li, Wei Dong Chi, and Zeng Min Shen. "Formation Mechanism and Microwave Permittivity of Carbon Nanotubes Filled with Metallic Silver Nanowires." Key Engineering Materials 334-335 (March 2007): 685–88. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.685.

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The filling of multi-walled carbon nanotubes (MWNTs) with metallic silver nanowires via wet chemistry method was investigated. The carbon nanotubes were filled with long continuous silver nanowires. The carbon nanotubes were almost opened and cut after being treated with concentrated nitric acid. Silver nitrate solution filled carbon nanotubes by capillarity. Carbon nanotubes were filled with silver nanowires after calcinations by hydrogen. The diameters of silver nanowires were in the range of 20-40nm, and lengths of 100nm-10μm. We studied the micromorphology of the silver nanowires filled in carbon nanotubes by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Based on the experimental results, a formation mechanism of the Ag nanowire-filled carbon nanotubes was proposed. And the microwave permittivity of the carbon nanotubes filled with metallic silver nanowires was measured in the frequency range from 2 GHz to 18 GHz. The loss tangent of the carbon nanotubes filled with metallic silver nanowires is high. So the carbon nanotubes filled with metallic silver nanowires would be a good candidate for microwave absorbent.

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Bajwa, Navdeep, Xuesong Li, Pulickel M. Ajayan, and Robert Vajtai. "Mechanisms for Catalytic CVD Growth of Multiwalled Carbon Nanotubes." Journal of Nanoscience and Nanotechnology 8, no. 11 (November 1, 2008): 6054–64. http://dx.doi.org/10.1166/jnn.2008.sw02.

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Carbon nanotubes possess unique properties that make them potentially ideal materials for various technological applications. However, a basic growth mechanism explaining the way metallic atoms interact with carbon to nucleate, grow and heal CNTs still needs to be understood. In this review paper we describe the mechanisms of catalytic chemical vapor deposition growth of multiwalled carbon nanotubes and carbon nanofibers, the role of various parameters that govern their growth kinetics and the knowledge added to singlewalled nanotube growth. We also examine future strategies needed to reveal complete knowledge of the growth mechanisms of carbon nanotubes.

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Singh, Rekha. "Transport Properties of Ordered and Disordered Doped Metallic Nanotubes." International Journal of Research in Engineering, Science and Management 3, no. 11 (November 8, 2020): 40. http://dx.doi.org/10.47607/ijresm.2020.368.

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We have studied the transport properties of ordered and disordered doped metallic nanotubes. We have presented these properties in periodic chemically metallic nitrogen doped metallic nanotubes. Transport properties with long range correlation have been studied using the Green’s function formalism in the frame work of the tight binding approach with effective parameters. Resonant conduction behaviour and ballistic transport have been demonstrated for particular positions of the dopant. These doping patterns have been shown to preserve the Bloach like transport properties and then to avoid Anderson localisation. The conductance response was almost changed because one of the two conductance channels remains true for both armchair and chiral nanotubes. These result reproduce the electronic properties of periodic nitrogen doped graphene. The present result has been drawn for specific chemical substitution of carbon atoms by nitrogen. These remain qualitatively valid for other local modifications of the nanotube by other chemical species by covalent or noncovalent functionalization. The energy of the quasi bound state depend on the specific local modification. We have shown that both axial and screw periodicities gave rise to such a behaviour and that specific disorder preserve their ballistic transport in doped metallic carbon nanotube.

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Gayduchenko, Igor, Georgy Fedorov, Ramil Ibragimov, Tatiana Stepanova, Arsen Gazaliev, Nikolay Vysochanskiy, Yuri Bobrov, Anton Malovichko, Ilya Sosnin, and Ivan Bobrinetskiy. "Synthesis of single-walled carbon nanotube networks using monodisperse metallic nanocatalysts encapsulated in reverse micelles." Chemical Industry 70, no. 1 (2016): 1–8. http://dx.doi.org/10.2298/hemind140910005g.

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We report on a method of synthesis of single-walled carbon nanotubes percolated networks on silicon dioxide substrates using monodisperse Co and Ni catalyst. The catalytic nanoparticles were obtained by modified method of reverse micelles of bis-(2-ethylhexyl) sulfosuccinate sodium in isooctane solution that provides the nanoparticle size control in range of 1 to 5 nm. The metallic nanoparticles of Ni and Co were characterized using transmission electron microscopy (TEM) and atomic-force microscopy (AFM). Carbon nanotubes were synthesized by chemical vapor deposition of CH4/H2 composition at temperature 1000 ?? on catalysts pre-deposited on silicon dioxide substrate. Before temperature treatment during the carbon nanotube synthesis most of the catalyst material agglomerates due to magnetic forces while during the nanotube growth disintegrates into the separate nanoparticles with narrow diameter distribution. The formed nanotube networks were characterized using AFM, scanning electron microscopy (SEM) and Raman spectroscopy. We find that the nanotubes are mainly single-walled carbon nanotubes with high structural perfection up to 200 ?m long with diameters from 1.3 to 1.7 nm consistent with catalyst nanoparticles diameter distribution and independent of its material.

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Дадашян, Л. Х., Р. Р. Трофимов, Н. Н. Конобеева, and М. Б. Белоненко. "Предельно короткие импульсы в оптически анизотропной среде, содержащей углеродные нанотрубки с металлической проводимостью." Оптика и спектроскопия 130, no. 12 (2022): 1861. http://dx.doi.org/10.21883/os.2022.12.54092.49-22.

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In this work, we study the interaction of extremely short pulses with a nonlinear anisotropic optical medium with carbon nanotubes (armchair and zigzag type) with metallic conductivity. The dependence of the pulse shape, width, and intensity on the nanotube chirality indices is analyzed. The most appropriate type of carbon nanotubes is substantiated for providing localized propagation of an electromagnetic field in a medium with anisotropic properties.

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Dresselhaus, M. S., and H. Dai. "Carbon Nanotubes: Continued Innovations and Challenges." MRS Bulletin 29, no. 4 (April 2004): 237–43. http://dx.doi.org/10.1557/mrs2004.74.

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AbstractThis article outlines the content of the April 2004 issue of MRS Bulletin on Advances in Carbon Nanotubes. Essentially, carbon nanotubes are self-assembling nanostructures constructed of sheets of hexagonal-shaped carbon atoms rolled up into cylinders. Carbon nanotubes have attracted a great deal of attention as model systems for nanoscience and for potential applications. The special interest in carbon nanotubes stems from their unique structure and properties: their very small size (down to ∼0.42 nm in diameter); the possibility for carbon nanotubes to be metallic or semiconducting, depending on their geometrical structure; their exceptional properties of ballistic transport; their extremely high thermal conductivity and high optical polarizability; and the possibilities of high structural perfection. Research in the carbon nanotube field has now advanced to the stage where a good understanding of the structure and many of the basic properties are in place, together with much appreciation of their interrelation. On the other hand, major gaps in basic knowledge remain, with the major obstacles confronting the carbon nanotube field being the lack of a detailed understanding of the nanotube growth mechanism and control of the synthesis process to produce nanotubes with a desired diameter and chirality. The brief review of the carbon nanotube field by leading experts in this issue comes at an opportune time. Many exciting results on the structural, electronic, optical, and transport properties of these tiny well-ordered structures have already been achieved, and the research is well enough developed to assess present progress and identify new research directions waiting to be explored.

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Zhang, A. Ying. "Advances of Study on the Developments and Applications of Carbon Nanotubes." Applied Mechanics and Materials 597 (July 2014): 36–39. http://dx.doi.org/10.4028/www.scientific.net/amm.597.36.

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Many electronic applications of carbon nanotubes crucially rely on techniques of selectively producing either semiconducting or metallic CNTs, preferably of certain chirality. Several methods of separating semiconducting and metallic CNTs are known, but most of them are not yet suitable for large-scale technological processes. The most efficient method relies on density-gradient ultracentrifugation, which separates surfactant-wrapped nanotubes by the minute difference in their density. This density difference often translates into difference in the nanotube diameter and (semi) conducting properties. Another method of separation uses a sequence of freezing, thawing, and compression of SWNTs embedded in agarose gel.

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Golnabi, Rustin, Su (Ike) Chih Chi, Stephen L. Farias, and Robert C. Cammarata. "A Continuous Flow Device for the Purification of Semiconducting Nanoparticles by AC Dielectrophoresis." MRS Proceedings 1700 (2014): 85–90. http://dx.doi.org/10.1557/opl.2014.850.

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ABSTRACTSingle-walled carbon nanotubes (SWCNTs) have attracted significant attention as building blocks for future nanoscale electronics due to their small size and unique electronic properties. However, current SWCNT production techniques generate a mixture of two types of nanotubes with divergent electrical behaviors due to structural variations. Some of the nanotubes act as metallic materials while others display semiconducting properties. This random mixture has prevented the realization of functional carbon nanotube-based nanoelectronics. Here, a method of purifying a continuous flow of semiconducting nanotubes from an initially random mixture of both metallic and semiconducting SWCNTs in suspension is presented. This purification uses A/C dielectrophoresis (DEP), and takes advantage of the large difference of the relative dielectric constants between metallic and semiconducting SWCNTs. Because of a difference in magnitude and opposite directions of a dielectrophoretic force imposed on the random SWCNT solution, metallic SWCNTs deposit onto an electrode while semiconducting SWCNTs remain in suspension [3]. A discussion of these techniques is presented, along with a dielectrophoretic force-utilized microfluidic lab-on-a-chip device that can accomplish purification of semiconducting nanoparticles at high processing rates. The effectiveness of the device is characterized using Raman spectroscopy analysis on separated samples.

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Zhao, Yanli, and Wenzhi Li. "Electrical Transport Properties of Multilayered Single-Walled Carbon Nanotube Films." Journal of Nanotechnology 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/601582.

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An improved layer-by-layer vacuum filtration method was adopted for the fabrication of single-walled carbon nanotube (SWCNT) films aiming at a series of SWCNT films with controllable thickness and density. The electrical transport properties of the multilayered SWCNT films have been investigated. With the constant film density, the decrease of the layer number of the SWCNT film results in an increase of the temperature coefficient of resistance (TCR). SWCNT film with 95% metallic nanotubes has shown a lower TCR than that of the SWCNT films with a low percentage of metallic nanotubes. The effect of thermal annealing and subsequent acid (HNO3) treatment on the electrical properties of the SWCNT films has also been investigated.

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Wan, Jian Feng, Yan Qiong Fei, and Jian Nong Wang. "Interaction between Carbon Nanotube and Mg Surface: Ab-Initio Investigation." Materials Science Forum 546-549 (May 2007): 481–84. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.481.

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ab-initio calculations on the interaction between the single-walled carbon nanotube (SWCN) and the Mg (0001) surface have been reported. It was found that the charge transfer from metal surfaces to the nanotubes takes place depending on both the electronic structures of the nanotubes and the work functions of the metal surfaces. The stable geometries for the nanotube between two consecutive objectives with C-Mg chemical bonds formed. The interaction energy in the most stable geometry is found to be CNT’s structural dependence. Concerning the electronic properties, the most stable structure showed a decrease in the density of states near the Fermi level due to the formation of C-Mg bonds enhancing the metallic character of the nanotube by the contact with the surface. The nature of the nanotube-interface interaction for nanotubes of larger diameters has been also discussed based on the calculated bond order.

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Yanagi, Kazuhiro. "(Digital Presentation) Strategy to Enhance the Power Factor in Carbon Nanotubes." ECS Meeting Abstracts MA2022-01, no. 7 (July 7, 2022): 644. http://dx.doi.org/10.1149/ma2022-017644mtgabs.

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Flexible thermoelectrics, which can convert waste heat into electricity at surfaces with various shapes and moving parts, is one of important techniques for efficient use of our limited energy resources. Carbon nanotubes are one of possible candidates for flexible thermoelectrics, and then we have investigated the relationships between electronic structure, location of Fermi-energy level, morphology, and thermoelectric performance of the carbon nanotubes. Particularly, we have clarified the one-dimensional characteristics in thermoelectric properties of single walled carbon nanotubes (SWCNTs). In the case of metallic SWCNTs, the thermoelectric trade-off is violated when the Fermi-energy level is tuned around van hove-singularity [1]. Thus, simultaneous enhancement of Seebeck coefficient and electrical conductivity is possible in the metallic type. In the case of semiconducting SWCNTs, we theoretically clarified that it is very difficult to identify the 1D characters in the properties of their Seebeck coefficient, power factor, and electrical conductivity. We found it is necessary to clarify the relationships between thermoelectrical conductivity (L12 term) and electrical conductivity (σ) to discuss the dimensionality in thermoelectric properties of semiconducting nanomaterials. We observed clear peak structure in the L12-σ plot in high-purity (6,5) SWCNT thin films, reflecting the 1D traces in semiconducting SWCNTs[2]. Morphology control is also important to enhance power factor of carbon nanotubes. The Seebeck coefficient does not depend on the directions of heat flow and nanotube axis, but the electrical conductivity can be enhanced when the current direction is parallel to the nanotube axis [1, 3]. On the basis of above characteristics, we determined the following strategy to enhance the power factor (PF) of SWCNTs. Fine tuning of Fermi-energy level in the metallic type of nanotube can enhance PF Aligned nanotubes with good electrical conductivity can enhance PF. Thus, we started to study the thermoelectric properties of carbon nanotube fibers with extremely good electrical conductivity, which are produced by Prof. Pasquali Group in Rice Univ [4]. As a result, we found the gigantic power factor of the nanotube fiber, which is 14 mWm-1K-2, with proper Fermi-level tuning [5]. Flexible thermoelectrics with such large PF will be useful for active cooling application. References: [1] Ichinose et al., Nano Lett. 19, 7370 (2019) [2] Ichinose et al., Phys. Rev. Mater. 5, 025404 (2021) [3] Fukuhara et al., Appl. Phys. Lett. 113, 243105 (2018) [4] Behabtu et al., Science 339, 182 (2013) [5] Komatsu et al. , Nature Comm. 12, 4931 (2021) Figure 1

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Dobrzańska-Danikiewicz, A. D., D. Łukowiec, D. Cichocki, and W. Wolany. "Comparison Of The MWCNTs-Rh And MWCNTs-Re Carbon-Metal Nanocomposites Obtained In High-Temperature." Archives of Metallurgy and Materials 60, no. 3 (September 1, 2015): 2053–60. http://dx.doi.org/10.1515/amm-2015-0348.

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Abstract Carbon-metal nanocomposites consisting of multiwalled carbon nanotubes coated with rhodium or rhenium nanoparticles by the high-temperature method were fabricated during the research undertaken. Multiwalled carbon nanotubes fabricated by Catalytic-Chemical Vapour Deposition (CCVD) were used in the investigations. Multiwalled carbon nanotubes functionalisation in acid or in a mixture of acids was applied to deposit rhodium or rhenium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of metallic nanoparticles. The material prepared was next subjected to high-temperature reduction in the atmosphere of argon and/or hydrogen to deposit rhodium or rhenium nanoparticles onto the surface of multiwalled carbon nanotubes. The investigations performed include, respectively: fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the material produced including examination of the structure and morphology, and the assessment of rhodium and/or rhenium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.

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Sreepad, H. R. "First-Principles Study of Dielectric Constant and Polarizability in Two Carbon Nanotubes." Asian Journal of Science and Applied Technology 7, no. 1 (May 5, 2018): 8–10. http://dx.doi.org/10.51983/ajsat-2018.7.1.1026.

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First-principles calculations have been carried out on two Carbon Nanotubes having 54 and 72 carbon atoms. The Electronic density of state reveals that the materials show metallic nature. Dielectric constant has been computed in case of Carbon Nanotubes C54 and C72. The value of dielectric constant in Carbon Nanotube C54 comes out to be 7.06, 6.28 and 14.53 along X, Y and Z axes respectively and its average value comes out to be 9.29. Value of dielectric constant in Carbon Nanotube C72 comes out to be 167, 168 and 737 along X, Y and Z axes respectively and its average value comes out to be 357. Polarizability of Carbon Nanotube C54 has been estimated and it comes out to be 116(Å)3, 111(Å)3 and 142(Å)3 along X, Y and Z axis respectively. Polarizability in case of Carbon Nanotube C72 comes out to be 171(Å)3, 171(Å)3 and 173(Å)3 along X, Y and Z axes respectively.

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Loayza, Cristhian RL, Paulo DC Assunção, Danyella CS Cardoso, Diego JA Borges, Ademir AC Filho, Marcos AL Reis, and Eduardo M. Braga. "Incorporation of AWS 316L wire nanostructured with nickel-carbon nanotube by arc welding." Journal of Composite Materials 52, no. 14 (October 17, 2017): 1899–906. http://dx.doi.org/10.1177/0021998317735880.

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Carbon nanotubes have certain properties, such as 150 GPa tensile strength, a 1000 GPa shear modulus, an electrical conductivity of 60 S/m, and a high thermal conductivity of 2500 W/mk, that make them an optimum metallic matrix composite reinforcement. Otherwise, arc welding is a common industrial process that joins almost all metals. However, there are hardly any studies involving the addition of carbon nanotubes in stainless steel so far. In this research, we show the incorporation of an AWS 316L nanostructured wire with nickel-carbon nanotubes in austenitic stainless steel via pulsed gas tungsten arc welding, which formed nanocomposites with 0.75 and 1.5 wt% carbon nanotube contents in the wire. The characterization was performed by scanning electronic microscope, Raman spectroscopy, and X-ray diffraction. The Vickers microhardness test was used to analyze the mechanical properties. The nanostructure composite had microstructure modification, and superficial microhardness improved in 35% for 0.75 wt% carbon nanotube.

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Pimenta, M. A., A. Marucci, S. A. Empedocles, M. G. Bawendi, E. B. Hanlon, A. M. Rao, P. C. Eklund, R. E. Smalley, G. Dresselhaus, and M. S. Dresselhaus. "Raman modes of metallic carbon nanotubes." Physical Review B 58, no. 24 (December 15, 1998): R16016—R16019. http://dx.doi.org/10.1103/physrevb.58.r16016.

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Thess, A., R. Lee, P. Nikolaev, H. Dai, P. Petit, J. Robert, C. Xu, et al. "Crystalline Ropes of Metallic Carbon Nanotubes." Science 273, no. 5274 (July 26, 1996): 483–87. http://dx.doi.org/10.1126/science.273.5274.483.

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Viet, Nguyen Ai, Hiroshi Ajiki, and Tsuneya Ando. "Lattice Instability in Metallic Carbon Nanotubes." Journal of the Physical Society of Japan 63, no. 8 (August 15, 1994): 3036–47. http://dx.doi.org/10.1143/jpsj.63.3036.

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Yoshioka, Hideo. "Oscillator Strength of Metallic Carbon Nanotubes." Journal of the Physical Society of Japan 70, no. 1 (January 15, 2001): 17–20. http://dx.doi.org/10.1143/jpsj.70.17.

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Ando, Tsuneya. "Dynamical Conductivity in Metallic Carbon Nanotubes." Journal of the Physical Society of Japan 71, no. 10 (October 15, 2002): 2505–11. http://dx.doi.org/10.1143/jpsj.71.2505.

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Suzuura, Hidekatsu, and Tsuneya Ando. "Weak-Localization in Metallic Carbon Nanotubes." Journal of the Physical Society of Japan 75, no. 2 (February 15, 2006): 024703. http://dx.doi.org/10.1143/jpsj.75.024703.

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Yokomichi, H., M. Matoba, T. Fukuhara, H. Sakima, F. Sakai, and K. Maezawa. "Are Boron-Doped Carbon Nanotubes Metallic?" physica status solidi (b) 207, no. 1 (May 1998): R1—R2. http://dx.doi.org/10.1002/(sici)1521-3951(199805)207:13.0.co;2-d.

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Gao, X. P., Y. Zhang, X. Chen, G. L. Pan, J. Yan, F. Wu, H. T. Yuan, and D. Y. Song. "Carbon nanotubes filled with metallic nanowires." Carbon 42, no. 1 (2004): 47–52. http://dx.doi.org/10.1016/j.carbon.2003.09.015.

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DEHGHANI, SAJJAD, MOHAMMAD KAZEM MORAVVEJ-FARSHI, and MOHAMMAD HOSSEIN SHEIKHI. "TEMPERATURE DEPENDENCE OF ELECTRICAL RESISTANCE OF INDIVIDUAL CARBON NANOTUBES AND CARBON NANOTUBES NETWORK." Modern Physics Letters B 26, no. 21 (July 16, 2012): 1250136. http://dx.doi.org/10.1142/s0217984912501369.

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We present a model to understand the effect of temperature on the electrical resistance of individual semiconducting single wall carbon nanotubes (s-SWCNTs) of various diameters under various electric fields. The temperature dependence of the resistance of s-SWCNTs and metallic SWCNTs (m-SWCNTs) are compared. These results help us to understand the temperature dependence of the resistance of SWCNTs network. We experimentally examine the temperature dependence of the resistance of random networks of SWCNTs, prepared by dispersing CNTs in ethanol and drop-casting the solution on prefabricated metallic electrodes. Examining various samples with different electrode materials and spacings, we find that the dominant resistance in determination of the temperature dependence of resistance of the network is the resistance of individual tubes, rather than the tube–tube resistance or tube–metal contact resistance. It is also found that the tube–tube resistance depends on the electrode spacing and it is more important for larger electrode spacings. By applying high electric field to burn the all-metallic paths of the SWCNTs network, the temperature dependence of the resistance of s-SWCNTs is also examined. We also investigate the effect of acid treatment of CNTs on the temperature dependence of the resistance of SWCNTs and also multi-wall CNTs (MWCNTs) networks.

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GREEN, F., and D. NEILSON. "ELECTRON GAS IN HIGH-FIELD NANOSCOPIC TRANSPORT: METALLIC CARBON NANOTUBES." International Journal of Modern Physics B 21, no. 13n14 (May 30, 2007): 2181–90. http://dx.doi.org/10.1142/s0217979207043579.

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Nanotube structures are unprecedented in their stability and current-carrying capacity at intense driving fields. A comprehensive understanding of electron conduction from equilibrium through to the high-driving-field regime is needed. We present a microscopically conserving quantum-kinetic description of transport for ohmically contacted carbon nanotubes. The approach is computationally straightforward and can describe nonequilibrium response over a wide range of parameters. We have analyzed the interplay of degeneracy and scattering dynamics on gate-controlled conduction in the one-dimensional channel, and have determined transconductances.

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Mateo-Mateo, Cintia, Carmen Vázquez-Vázquez, Moisés Pérez-Lorenzo, Verónica Salgueiriño, and Miguel A. Correa-Duarte. "Ostwald Ripening of Platinum Nanoparticles Confined in a Carbon Nanotube/Silica-Templated Cylindrical Space." Journal of Nanomaterials 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/404159.

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Sintering of nanoparticles mediated by an Ostwald ripening mechanism is generally assessed examining the final particle size distributions. Based on this methodology, a general approach for depositing platinum nanoparticles onto carbon nanotubes in solution has been employed in order to evaluate the sintering process of these metallic nanoparticles at increasing temperatures in a carbon nanotube/silica-templated confined space.

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Uchino, Takashi, Greg Ayre, David Smith, John Hutchison, C. de Groot, and Peter Ashburn. "The Effects of Hydrogen Annealing on Carbon Nanotube Field-Effect Transistors." Nanomaterials 11, no. 10 (September 23, 2021): 2481. http://dx.doi.org/10.3390/nano11102481.

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We have systematically investigated the effects of hydrogen annealing on Ni- and Al-contacted carbon nanotube field-effect transistors (CNTFETs), whose work functions have not been affected by hydrogen annealing. Measured results show that the electronic properties of single-walled carbon nanotubes are modified by hydrogen adsorption. The Ni-contacted CNTFETs, which initially showed metallic behavior, changed their p-FET behavior with a high on-current over 10 µA after hydrogen annealing. The on-current of the as-made p-FETs is much improved after hydrogen annealing. The Al-contacted CNTFETs, which initially showed metallic behavior, showed unipolar p-FET behavior after hydrogen annealing. We analyzed the energy band diagrams of the CNTFETs to explain experimental results, finding that the electron affinity and the bandgap of single-walled carbon nanotubes changed after hydrogen annealing. These results are consistent with previously reported ab initio calculations.

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Li, Xia, Dong Lin Zhao, and Zeng Min Shen. "Microstructure and Formation Mechanism of Carbon Nanotubes Filled with Metallic Silver Nanowires." Advanced Materials Research 11-12 (February 2006): 587–90. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.587.

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The filling of multi-walled carbon nanotubes with metallic silver nanowires via wet chemistry method was investigated. The carbon nanotubes were filled with long continuous silver nanowires. The carbon nanotubes were almost opened and cut after being treated with concentrated nitric acid. Silver nitrate solution filled carbon nanotubes by capillarity. Carbon nanotubes were filled with silver nanowires after calcinations by hydrogen. The diameters of silver nanowires were in the range of 20-40 nm, and lengths of 100 nm - 10 μm. We studied the micromorphology of the silver nanowires filled in carbon nanotubes by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Based on the experimental results, a formation mechanism of the Ag nanowire-filled carbon nanotubes was proposed.

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Prathap Naik, Mude Gnani. "CARBON NANOTUBE COMPUTER." International Journal of Engineering Applied Sciences and Technology 7, no. 7 (November 1, 2022): 172–75. http://dx.doi.org/10.33564/ijeast.2022.v07i07.027.

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Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources; hydrogen storage media; and probes, and interconnects. Some of these applications are now realized in products. Others are demonstrated in early to advanced devices, and nanometer-sized semiconductor devices is one such application. Nanotube cost, polydispersity in nanotube type, and limitations in processing and assembly methods are important barriers for some applications of single-walled nanotubes. Problem is, carbon nanotubes aren't perfect either. They don't always grow in perfectly straight lines, and a fraction of the tubes grown aren't able to "switch off" like a regular transistor. The Stanford team used a technique of "burning" off some of the imperfect carbon nanotubes while also working their way around other imperfections by using a complex algorithm. They do not, for example, always grow in parallel lines, which has led researchers to devise techniques to grow 99.5 percent of CNTs in straight lines, according to the press release. But with billions of nanotubes on a chip, even a small misalignment of the tubes can cause errors. A fraction of the CNTs also behave like metallic wires that always conduct electricity, instead of acting like semiconductors that can be switched off. The final design consists of a very basic computer with 178 transistors that can do tasks like counting and number sorting and switch between functions. The rise of carbon nanotube computers in the future is for sure and the basic algorithm to prove this concept is illustrated in depth. CNTs are prominent among a variety of emerging technologies that are being considered for the next generation of highly energy efficient electronic systems.This may take some time to make this kind of computer designed by using nanotubes available for all but once it is developed it is going to lead to a new era in the world of computers.

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McCANN, EDWARD, and VLADIMIR I. FAL'KO. "SYMMETRY PROPERTIES OF IMPURITIES IN METALLIC SINGLE-WALL CARBON NANOTUBES." International Journal of Modern Physics B 18, no. 23n24 (October 10, 2004): 3195–212. http://dx.doi.org/10.1142/s021797920402641x.

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We use the effective mass model to describe spinless electrons near the Fermi level in metallic, single-wall carbon nanotubes. Taking into account two nonequivalent valleys (K-points) produces a four component Dirac equation for massless fermions, with the role of spin assumed by pseudospin due to the relative amplitude of the wavefunction on the two nonequivalent sublattice atoms. We show that the position of a short-ranged impurity within the hexagonal graphite unit cell produces a particular 4×4 matrix structure of the corresponding effective Hamiltonian. The symmetry of this Hamiltonian with respect to pseudospin flip is related to degeneracy breaking and, for an armchair tube, symmetry with respect to mirror reflection in the nanotube axis is related to pseudospin mixing. In a nanotube of finite length, we predict a sinusoidal oscillation of energy level shift as a function of energy with a period determined by the position of the impurity along the tube axis.

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FUJITA, S., Y. TAKATO, and A. SUZUKI. "THEORY OF THE ELECTRICAL TRANSPORT IN METALLIC SINGLE-WALL NANOTUBES." Modern Physics Letters B 25, no. 04 (February 10, 2011): 223–42. http://dx.doi.org/10.1142/s0217984911025675.

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A metallic (semiconducting) single-wall nanotube contains an irrational (integral) number of carbon hexagons in the pitch. The room-temperature conductivity is higher by two to three orders of magnitude in metallic nanotubes than in semiconducting nanotubes. Tans et al. [Nature386 (1997) 474] measured the electrical currents in metallic single-wall carbon nanotubes under bias and gate voltages, and observed non-Ohmic behaviors. The original authors interpreted their data in terms of a ballistic transport due to the Coulomb blockage on the electron-carrier model. The mystery of why a ballistic electron is not scattered by impurities and phonons is unexplained, however. An alternate interpretation is presented based on the Cooper pair (pairon)–carrier model. Superconducting states are generated by the Bose–Einstein condensation of the ± pairons at momenta 2πℏn/L, where L is the tube length and n a small integer. As the gate voltage changes the charging state of the tube, the superconducting states jump between different n. The normal current peak shapes appearing in the transition are found to be temperature-dependent, which is caused by the electron–optical phonon scattering.

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Moshkalev, S. A., J. Leon, Carla Veríssimo, A. R. Vaz, A. Flacker, M. B. de Moraes, and J. W. Swart. "Controlled Deposition and Electrical Characterization of Multi-Wall Carbon Nanotubes." Journal of Nano Research 3 (October 2008): 25–32. http://dx.doi.org/10.4028/www.scientific.net/jnanor.3.25.

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A method of ac dielectrophoresis was applied to align and deposit metallic multi-wall carbon nanotubes between pre-fabricated metal (Au, Pd) electrodes with a micron scale separation. For improvement of nanotube contacts with electrodes, Ni and Pd electroless processes were developed, and significant reduction of 2 terminals resistances was demonstrated. Further, using electron and ion beam deposited Pt contacts in two different configurations (“Pt-on-CNT” and “CNT-on-Pt”), 4 terminals measurements have been performed to evaluate intrinsic nanotube resistances. The values between 90 and 130 kΩ/μm were obtained, while systematically lower values (30-70 kΩ/μm) were estimated using 2 terminals method. The 4 terminals method was applied to study the effect of ion irradiation on the electrical parameters of supported nanotubes.

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Dobrzańska-Danikiewicz, A. D., D. Cichocki, and D. Łukowiec. "The MWCNTs-Rh Nanocomposite Obtained By The New High-Temperature Method." Archives of Metallurgy and Materials 60, no. 2 (June 1, 2015): 1057–63. http://dx.doi.org/10.1515/amm-2015-0259.

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AbstractA nanocomposite was fabricated during the research undertaken, consisting of multiwalled carbon nanotubes coated with rhodium nanoparticles by the new high-temperature method being the subject of the patent claim. High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100÷500 nm and the diameter of 8÷20 nm obtained in advance with Catalytic Chemical Vapour Deposition (CVD) were employed in the investigations. The nanotubes manufactured under the own research contain small amounts of metallic impurities and amorphous carbon deposits. Multiwalled carbon nanotubes functionalisation in acids was applied to deposit rhodium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of rhodium nanoparticles. The material prepared was next placed in a quartz vessel and subjected to high-temperature reduction in the atmosphere of argon to deposit rhodium nanoparticles onto the surface of multiwalled carbon nanotubes. The following examinations were performed, respectively: MWCNTs fabrication, fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the materials produced including examination of the structure and morphology, and the assessment of rhodium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.

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Smith, Brian W., and David E. Luzzi. "Encapsulated Fullerenes Within Single Wall Carbon Nanotubes." Microscopy and Microanalysis 5, S2 (August 1999): 182–83. http://dx.doi.org/10.1017/s1431927600014239.

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It is well documented that the pulsed laser vaporization of graphite produces both carbon nanotubes and C60 in the presence of certain metallic catalysts. In nanotube production most of the Ceo is removed along with other residual contaminants during succeeding purification and annealing steps. The possibility of C60 becoming trapped inside a nanotube during this elaborate sequence has been considered but not previously detected.Nanotubes are observed with high resolution transmission electron microscopy under conditions chosen to minimize both exposure time and irradiation damage. Since a nanotube satisfies the weak phase object approximation, its image is a projection of the specimen -potential in the direction of the electron beam. The image has maximum contrast where the beam encounters the most carbon atoms, which occurs where it is tangent to the tube’s walls. Thus, the image consists of two dark parallel lines whose separation is equal to the tube diameter, 1.4 nm.

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NAKASHIMA, NAOTOSHI. "SOLUBLE CARBON NANOTUBES: FUNDAMENTALS AND APPLICATIONS." International Journal of Nanoscience 04, no. 01 (February 2005): 119–37. http://dx.doi.org/10.1142/s0219581x05002985.

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Carbon nanotubes (CNTs) have been in the forefront of nanoscience and nanotechnology because of their remarkable electronic, mechanical, and thermal properties and specific functions. CNTs have high potentials for possible applications in the fields of energy, electronics, IT, and materials. However, because of the insolubility of the nanotubes in solvents, chemical, biochemical, and biological (medical) approaches using these materials have been rather limited. Soluble CNTs in aqueous and organic systems are of interests since they may open the door in such fields. In this review article, (i) the dissolution of CNTs in water and in organic solvents by using chemical modification and physical adsorption and their applications to chemical and biological areas, (ii) separation of metallic SWNTs and semiconducting SWNTs by the combination of individual dissolution of SWNTs and the selective chemical modification, (iii) the preparation of nanotube films and fibers from dissolved/dispersed SWNTs in aqueous micelles, and (iv) CNT liquid crystal formation are summarized.

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Strobl, Karlheinz, and Fahd Rajab. "Water-Assisted Catalytic VACNT Growth Optimization for Speed and Height." Processes 11, no. 6 (May 23, 2023): 1587. http://dx.doi.org/10.3390/pr11061587.

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The super-growth approach for carbon nanotubes synthesis is frequently used to boost the growth rate, catalyst lifespan, and height of vertically aligned carbon nanotubes. The elimination of amorphous carbon from catalyst particles, commonly made of iron, by injecting water vapor into a chemical vapor deposition process can enhance the purity, alignment, and height of carbon nanotubes and prevent the partial oxidation of the metallic catalyst. We present the development of a modified growth-optimized water-assisted super-growth vertically aligned carbon nanotube process by optimizing the catalyst layer structure and water vapor concentration for a carbon nanotube growth process for 4” diameter Si wafers. A significant finding is that under optimized water-assisted growth conditions over 4 mm, highly uniform tall, vertically aligned carbon nanotube structures can be grown with a minimum top crust layer of about ~5–10 μm thickness. This was achieved with a catalyst film comprising a >400 mm thermal SiO2 layer on top of a 4” diameter Si wafer that was overcoated with an e-beam batch process run that first deposited a 20 nm SiO2 layer, a 10 nm Al2O3 layer, and a 1.1 nm Fe layer, in a 4-h growth process step.

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Dobrzańska-Danikiewicz, A. D., D. Cichocki, and D. Łukowiec. "Nanocomposites Consisting of Carbon Nanotubes and Nanoparticles of Noble Metals." Materials Science Forum 879 (November 2016): 442–47. http://dx.doi.org/10.4028/www.scientific.net/msf.879.442.

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In the framework of the made researches nanocomposite of CNT-NPs type (Carbon Nanotube-Nanoparticles) consisting of multiwalled carbon nanotubes coated by rhodium nanoparticles and/or palladium using the two-step indirect method: chemical reduction have been produced. In the researches high-quality multi-walled carbon nanotubes MWCNTs with a length of 100 to 500 nm and a diameter of 8 to 20 nm previously obtained in the catalytic-chemical vapour deposition CCVD have been used. Nanotubes produced within the framework of own researches contain minor amounts of metallic impurities and amorphous carbon deposits. In order to deposit the noble metal nanoparticles on the surface of carbon nanotubes functionalization of multi-walled carbon nanotubes in a mixture of H2SO4 and HNO3 acids have been used. The prepared material has been subjected chemical reduction using noble metal precursors (RhCI3, PdCl2). The characterization of the produced material including the examination of the structure, morphology, chemical composition and evaluation of the size and distribution of rhodium and/or palladium nanoparticles on the surface of carbon nanotubes has been performed using: scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS). The produced nanomaterials may be used as the active layer of sensors of chemical/biological agents.

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Jovanovic, Svetlana, Zoran Markovic, Duska Kleut, Dragana Tosic, Dejan Kepic, Milena Marinovic-Cincovic, Ivanka Holclajtner-Antunovic, and Biljana Todorovic-Markovic. "Covalent modification of single wall carbon nanotubes upon gamma irradiation in aqueous media." Chemical Industry 65, no. 5 (2011): 479–87. http://dx.doi.org/10.2298/hemind110531050j.

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Single wall carbon nanotubes (SWCNTs) were exposed to gamma radiation, absorbing the doses of 25, 50 and 100 kGy in aqueous environment. After the irradiation treatment, the changes in the structure were studied using Fourier Transform Infrared and Raman spectroscopy, thermogravimetric analysis and atomic force microscopy. Fourier Transform Infrared Spectroscopy has shown that the irradiation of SWCNTs in aqueous environment leads to covalent functionalization of SWCNTs. The irradiation of water leads to its radiolysis and the formation of free radical species of different types. These species react with nanotube sidewalls and in such way carboxylic and hydroxylic groups are covalently bonded to the sidewalls of SWCNTs. Thermogravimetric analysis was used to estimate the total amount of covalently bonded groups. The highest ratio of covalently bonded groups appears in nanotubes irradiated with the 100 kGy dose. Raman spectroscopy proves that the increase in irradiation doses leads to an increase of structural disorder of SWCNTs, presumably in the form of defects in carbon nanotube walls. Examination of ID to IG ratio shows a three times larger degree of structural disorder after the irradiation treatment with 100 kGy. The analysis of carbon nanotube Raman spectra RBM bands determined the presence of both semiconducting and metallic carbon nanotubes after gamma irradiation treatment. These measurements prove that gamma irradiation treatments have a nonselective effect regarding different chirality and therefore conductance of nanotubes. Atomic force microscopy shows a significant carbon nanotube shortening as the effect of gamma radiation treatment. Nanotubes with length between 500 nm and 1 ?m are predominant.

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Zou, Xiao Ping, H. Abe, Toru Shimizu, A. Ando, H. Tokumoto, S. M. Zhu, and Hao Shen Zhou. "Chemical Vapor Deposition Growth of Multi-Walled Carbon Nanotubes on Metallic Substrates." Solid State Phenomena 121-123 (March 2007): 101–4. http://dx.doi.org/10.4028/www.scientific.net/ssp.121-123.101.

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A simple thermal chemical vapor deposition (STCVD) growth technique of multi-walled carbon nanotubes (MWCNTs) is present. Carbon nanotube film was synthesized on the Pt plate substrates by pyrolysis of ethyl alcohol as carbon source at lower reaction temperature at atmospheric pressure by using simple apparatus. The as-synthesized MWCNTs were characterized by both scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The electrical property of an individual MWCNT was evaluated by I-V measurement. The electrical resistance of single MWCNT is about 450 k/ in linear region under bias voltage between 2 to 4 V. It can undergo a large current of 6 2A at 4 V

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TSUJI, NAOTO, SHIGEHIRO TAKAJO, and HIDEO AOKI. "LARGE MAGNETIC MOMENTS GENERATED FROM LOOP CURRENTS IN CARBON NANOTUBE ATTACHED TO ELECTRODES — A THEORETICAL PICTURE." International Journal of Modern Physics B 21, no. 08n09 (April 10, 2007): 1198–206. http://dx.doi.org/10.1142/s021797920704263x.

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Inspired by a recent experiment which has detected a large orbital magnetic moment when electrodes are attached to a carbon nanotube, we study the ballistic transport in metallic carbon nanotubes when a current is injected from electrodes with finite bias voltages with nonequilibrium Green's function method. We reveal, both analytically and numerically, that large loop currents circulating around the tube are induced, which come from a quantum mechanical interference, when the injected electron is resonant with a time-reversed pair of degenerate states inherent in the zigzag and chiral nanotubes. This results in large orbital magnetic moments, making the nanotube a molecular solenoid. The current distribution for various types of tube and the magnetic moment as a function of the bias are displayed.

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Lin, Yi-Ni, Li Ma, Quan Yang, Song-Chao Geng, Mao-Sheng Ye, Tao Chen, and Li-Ning Sun. "Electron transport properties of carbon nanotubes with radial compression deformation." Acta Physica Sinica 71, no. 2 (2022): 027301. http://dx.doi.org/10.7498/aps.71.20211370.

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In this paper, molecular dynamics simulation method is used to investigate the contacting configuration of carbon nanotubes with open ends and metal, thereby obtaining the law of radial compression deformation of carbon nanotubes. The obtained results show that after horizontally contacting the metal surface, the radial compression deformation is affected by the contact length, the diameter of the tube, the type of metal and the number of layers. Based on the first principles combining tight-binding density functional theory and non-equilibrium Green's function, the electron transport properties of carbon nanotubes with different diameters, chiralities, lamellar deformations and radial deformations are systematically studied. The obtained results show that the current of metallic single-walled carbon nanotubes presents linear change in a bias voltage range between –2 V and 2 V, and the current-voltage curve is symmetrical about the origin. The magnitude of the current is only related to the bias voltage, but not to the diameter; when the carbon nanotubes are deformed by radial compression, the current growth trend is downward and even plateau effect may appear under a larger bias voltage. The current flowing in the semiconducting single-walled carbon nanotubes decreases with the increase of radial compression deformation, and the current-voltage curve gradually transforms from semiconductor characteristics into metallic characteristics. The trend of the current-voltage curve of double-walled carbon nanotubes is consistent with that of metallic single-walled carbon nanotubes. However, the non-linear variation amplitude of the current-voltage curve of double-walled carbon nanotubes is less affected by the radial compression deformation. Owing to the increase of walls of nanotubes, the current of double-walled carbon nanotubes is twice as high as that of single-walled carbon nanotubes under the same bias voltage. The electrons can produce transitions through rapid vibration between adjacent tubes, in view of the fact that interlayer coupling characteristics of three-walled carbon nanotubes reduce the degeneracy of the energy level and larger system increases the density of states near the Fermi level, resulting in large oscillations and asymmetry about the origin of the current-voltage curve.

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Nshimiyimana, Jean Pierre, Jian Zhang, Xiannian Chi, Xiao Hu, Pei Wu, Siyu Liu, Jia Liu, Weiguo Chu, and Lianfeng Sun. "Large positive magnetoresistance in semiconducting single-walled carbon nanotubes at room temperature." RSC Advances 8, no. 19 (2018): 10179–84. http://dx.doi.org/10.1039/c8ra00877a.

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Zdrojek, M., W. Gebicki, C. Jastrzebski, T. Melin, and A. Huczko. "Studies of Multiwall Carbon Nanotubes Using Raman Spectroscopy and Atomic Force Microscopy." Solid State Phenomena 99-100 (July 2004): 265–68. http://dx.doi.org/10.4028/www.scientific.net/ssp.99-100.265.

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Preliminary results of Raman scattering measurements of multiwall carbon nanotubes (MWCNT) are presented. The nanotubes have been carefully dissolved, separated and then characterized by AFM. The micro-Raman spectra are taken with 514,5nm wavelength excitations in the range 4K - 400K. Basically the spectra are quite similar to the well known single wall carbon nanotube spectra, but the low frequency band is absent. The major Raman bands, observed in single wall nanotubes are found in the spectra. In particular the disorder effects are visible due to the pronounced D band at ~1350 cm-1. Metallic and semiconducting type of conductivity is distinguished through analysis of the G (LO) mode at ~1600 cm-1. A new feature in these spectra exists at ~843 cm-1. Low energy radial breathing mode absence has been explained.

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Révész, Ádám, Marcell Gajdics, Miratul Alifah, Viktória Kovács Kis, Erhard Schafler, Lajos Károly Varga, Stanislava Todorova, Tony Spassov, and Marcello Baricco. "Thermal, Microstructural and Electrochemical Hydriding Performance of a Mg65Ni20Cu5Y10 Metallic Glass Catalyzed by CNT and Processed by High-Pressure Torsion." Energies 15, no. 15 (August 5, 2022): 5710. http://dx.doi.org/10.3390/en15155710.

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A Mg65Ni20Cu5Y10 metallic glass was produced by melt spinning and was mixed with a 5 wt.% multiwall carbon nanotube additive in a high-energy ball mill. Subsequently, the composite mixture was exposed to high-pressure torsion deformation with different torsion numbers. Complimentary XRD and DSC experiments confirmed the exceptional structural and thermal stability of the amorphous phase against severe plastic deformation. Combined high-resolution transmission electron microscopy observations and fast Fourier transform analysis revealed deformation-induced Mg2Ni nanocrystals, together with the structural and morphological stability of the nanotubes. The electrochemical hydrogen discharge capacity of the severely deformed pure metallic glass was substantially lower than that of samples with the nanotube additive for several cycles. It was also established that the most deformed sample containing nanotubes exhibited a drastic breakdown in the electrochemical capacity after eight cycles.

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KHABAZIAN, SIAVASH, and SOHRAB SANJABI. "PRELIMINARY STUDY OF ELECTROPHORETIC DEPOSITION OF VERTICALLY ALIGNED MWCNT ON METALLIC ELECTRODE." International Journal of Modern Physics: Conference Series 05 (January 2012): 704–11. http://dx.doi.org/10.1142/s2010194512002656.

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Multi-walled carbon nanotubes films formed randomly aligned laterally by electrophoresis. Multi-walled carbon nanotubes with lengths of about 10 μ was shortened and functionalized by a mixture of sulfuric and nitric acid. The functional groups on carbon nanotubes were elaborated by FT-IR. Chemically shortened MWCNTs disperse in organic and aqueous solvent and deposited on electrode vertically-aligned by applying a constant DC electric field. The alignment of MWCNTs was observed by scanning electron microscopy. It also the effect of various substrates on alignment of multi-walled carbon nanotubes was investigated.

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Araujo, Karolline A. S., Ana P. M. Barboza, Thales F. D. Fernandes, Nitzan Shadmi, Ernesto Joselevich, Mario S. C. Mazzoni, and Bernardo R. A. Neves. "Charge transfer between carbon nanotubes on surfaces." Nanoscale 7, no. 39 (2015): 16175–81. http://dx.doi.org/10.1039/c5nr03547c.

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Journal articles on the topic 'METALLIC CARBON NANOTUBES'

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