Bundlet Model for Single-Wall Carbon Nanotubes, Nanocones and Nanohorns

Carbon Nanocones ◽

This paper discusses the existence of single-wall carbon nanocones (SWNCs), especially nanohorns (SWNHs), in organic solvents in the form of clusters. A theory is developed based on a bundlet model describing their distribution function by size. Phenomena have a unified explanation in bundlet model in which free energy of an SWNC, involved in a cluster, is combined from two components: a volume one, proportional to number of molecules n in a cluster, and a surface one proportional to n1/2. Bundlet model enables describing distribution function of SWNC clusters by size. From purely geometrical differences, bundlet (SWNCs) and droplet (fullerene) models predict different behaviours. The SWNCs of various disclinations are investigated via energetic–structural analyses. Several SWNC’s terminations are studied, which are different among one another because of type of closing structure and arrangement. The packing efficiencies and interaction-energy parameters of SWNCs/SWNHs are intermediate between fullerene and single-wall carbon nanotube (SWNT) clusters; an in-between behaviour is expected. However, the properties of SWNCs, especially SWNHs, are calculated close to SWNTs. The structural asymmetry in the different SWNCs, entirely characterized by their cone angle, distinguishes the properties of some, such as P2.

Cluster Origin of Solvent Features of Fullerenes, Single-Wall Carbon Nanotubes, Nanocones, and Nanohorns

Nanotechnology ◽

10.4018/978-1-4666-5125-8.ch011 ◽

2014 ◽

pp. 262-318

Author(s):

Francisco Torrens ◽

Gloria Castellano

Keyword(s):

Carbon Nanotubes ◽

Free Energy ◽

Distribution Function ◽

Carbon Nanotube ◽

Interaction Energy ◽

Organic Solvents ◽

Single Wall Carbon Nanotube ◽

Carbon Nanocones ◽

This chapter discusses the existence of single-wall carbon nanocones (SWNCs), especially nanohorns (SWNHs) in organic solvents in the form of clusters. A theory is developed based on a bundlet model describing their distribution function by size. Phenomena have a unified explanation in bundlet model in which free energy of an SWNC, involved in a cluster, is combined from two components: a volume one, proportional to number of molecules n in a cluster, and a surface one proportional to n1/2. A bundlet model enables describing distribution function of SWNC clusters by size. From purely geometrical differences, bundlet (SWNCs) and droplet (fullerene) models predict different behaviours. The SWNCs of various disclinations are investigated via energetic–structural analyses. Several SWNC’s terminations are studied which are different among one another because of the type of closing structure and arrangement. Packing efficiencies and interaction-energy parameters of SWNCs/SWNHs are intermediate between fullerene and single-wall carbon nanotube (SWNT) clusters.

Cluster Origin of Solvent Features of Fullerenes, Single-Wall Carbon Nanotubes, Nanocones, and Nanohorns

Nanoscience and Advancing Computational Methods in Chemistry ◽

10.4018/978-1-4666-1607-3.ch001 ◽

2012 ◽

pp. 1-57

Author(s):

Francisco Torrens ◽

Gloria Castellano

Keyword(s):

Carbon Nanotubes ◽

Free Energy ◽

Distribution Function ◽

Carbon Nanotube ◽

Interaction Energy ◽

Organic Solvents ◽

Single Wall Carbon Nanotube ◽

Carbon Nanocones ◽

This chapter discusses the existence of single-wall carbon nanocones (SWNCs), especially nanohorns (SWNHs) in organic solvents in the form of clusters. A theory is developed based on a bundlet model describing their distribution function by size. Phenomena have a unified explanation in bundlet model in which free energy of an SWNC, involved in a cluster, is combined from two components: a volume one, proportional to number of molecules n in a cluster, and a surface one proportional to n1/2. A bundlet model enables describing distribution function of SWNC clusters by size. From purely geometrical differences, bundlet (SWNCs) and droplet (fullerene) models predict different behaviours. The SWNCs of various disclinations are investigated via energetic–structural analyses. Several SWNC’s terminations are studied which are different among one another because of the type of closing structure and arrangement. Packing efficiencies and interaction-energy parameters of SWNCs/SWNHs are intermediate between fullerene and single-wall carbon nanotube (SWNT) clusters.

Advances in Systems Analysis, Software Engineering, and High Performance Computing - Contemporary Advancements in Information Technology Development in Dynamic Environments ◽

Nanostructures Cluster Models in Solution

10.4018/978-1-4666-6252-0.ch012 ◽

2014 ◽

pp. 221-253 ◽

Cited By ~ 1

Author(s):

Francisco Torrens ◽

Gloria Castellano

Keyword(s):

Free Energy ◽

Distribution Function ◽

Boron Nitride ◽

Interaction Energy ◽

Size Distribution ◽

Cone Angle ◽

Size Distribution Function ◽

Cluster Models ◽

Structural Asymmetry ◽

Energy Parameters

The existence of Single-Wall C-Nanocones (SWNCs), especially nanohorns (SWNHs), and BC2N/Boron Nitride (BN) analogues in cluster form is discussed in solution in this chapter. Theories are developed based on models bundlet and droplet describing size-distribution function. The phenomena present unified explanation in bundlet in which free energy of (BC2N/BN-)SWNCs involved in cluster is combined from two parts: volume one proportional to the number of molecules n in cluster and surface one, to n1/2. Bundlet enables describing distribution function of (BC2N/BN-)SWNC clusters by size. From geometrical differences bundlet [(BC2N/BN-)SWNCs] and droplet (C60/B15C30N15/B30N30) predict dissimilar behaviours. Various disclination (BC2N/BN-)SWNCs are studied via energetic and structural analyses. Several (BC2N/BN-)SWNC's ends are studied that are different because of closing structure and arrangement type. Packing efficiencies and interaction-energy parameters of (BC2N/BN-)SWNCs/SWNHs are intermediate between C60/B15C30N15/B30N30 and (BC2N/BN-)Single-Wall C-Nanotube (SWNT) clusters: in-between behaviour is expected; however, properties of (BC2N/BN-)SWNCs, especially (BC2N/BN-)SWNHs, are calculated closer to (BC2N/BN-)SWNTs. Structural asymmetry in different (BC2N/BN-)SWNCs characterized by cone angle distinguishes properties of types: P2. BC2N/BN, especially species isoelectronic with C-analogues may be stable.

Preparation of a Functional Enzyme–Carbon Nanotube Complex by the Immobilization of Superoxide Dismutase on Single-Wall Carbon Nanotubes

Nanotechnologies in Russia ◽

10.1134/s1995078018040134 ◽

2018 ◽

Vol 13 (7-8) ◽

pp. 349-355 ◽

Cited By ~ 1

Author(s):

D. K. Shishkova ◽

Yu. I. Khodyrevskaya ◽

A. G. Kutikhin ◽

M. S. Rybakov ◽

R. A. Mukhamadiyarov ◽

...

Keyword(s):

Carbon Nanotubes ◽

Superoxide Dismutase ◽

Carbon Nanotube ◽

Self-Assembly Fabrication of High Performance Carbon Nanotubes Based FETs

MRS Proceedings ◽

10.1557/proc-772-m4.7 ◽

2003 ◽

Vol 772 ◽

Cited By ~ 5

Author(s):

Emmanuel Valentin ◽

Stephane Auvray ◽

Arianna Filoramo ◽

Aline Ribayrol ◽

Marcelo Goffman ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Self Assembly ◽

High Performance ◽

Field Effect Transistors ◽

High Yield ◽

Single Wall Carbon ◽

Assembled Monolayers ◽

Self Assembled

AbstractWe describe the realization of high quality self-assembled single wall carbon nanotube field effect transistors (CNTFET). A method using self-assembled monolayers (SAMs) is used to obtain high yield selective deposition placement of single wall carbon nanotubes (SWNTs) on predefined regions of a substrate. This is achieved with individual or small bundles of SWNTs and with high densities suitable for fabrication of integrated devices. We show that such positioned SWNTs can be electrically contacted to realize high performance transistors, which very well compare with state-of-the-art CNTFETs. We therefore validate the self-assembly approach to reliably fabricate efficient carbon nanotube based devices.

Electrochemical Tuning of Single-Wall Carbon Nanotube Mat and Investigations on Actuator Mechanism

MRS Proceedings ◽

10.1557/proc-855-w3.2 ◽

2004 ◽

Vol 855 ◽

Author(s):

S. Gupta ◽

M. Hughes ◽

J. Robertson

Keyword(s):

Carbon Nanotubes ◽

Charge Transfer ◽

Carbon Nanotube ◽

Bond Length ◽

Upper Bound ◽

Single Wall Carbon Nanotube ◽

Single Wall Carbon ◽

Electrochemical Tuning

ABSTRACTElectrochemical tuning of single-wall carbon nanotubes has been investigated using in situ Raman spectroscopy. We built a linear actuator from single-wall carbon nanotube mat and studied in several alkali metal (Li, Na, and K) and alkaline earth (Ca) halide solutions. The variation of bonding with electrochemical biasing was monitored using in situ Raman. This is since Raman can detect changes in C-C bond length: the radial breathing mode (RBM) at ∼190 cm−1 varies inversely with the nanotube diameter and the G band at ∼1590 cm−1 varies with the axial bond length. In addition, the intensities of both the modes vary significantly in a nonmonotonic manner pointing at the emptying/depleting or filling of the bonding and anti-bonding states - electrochemical charge injection. We discuss the variation of spectroscopic observables (intensity/frequency) of these modes providing valuable information on the charge transfer dynamics on the single-wall carbon nanotubes mat surface. We found the in-plane compressive strain (∼ -0.25%) and the charge transfer per carbon atom (fc ∼ -0.005) as an upper bound for the electrolytes used i.e. CaCl2. These results can be quantitatively understood in terms of the changes in the energy gaps between the one-dimensional van Hove singularities in the electron density of states arising possibly due to the alterations in the overlap integral of π bonds between the p orbitals of the adjacent carbon atoms. Moreover, the extent of variation of the absolute potential of the Fermi level or alternatively modification of band gap is estimated from modeling Raman intensity to be around 0.1 eV as an upper bound for CaCl2.

Electrical Resistance of Single-Wall Carbon Nanotubes with Determined Chiral Indices

MRS Proceedings ◽

10.1557/proc-1204-k07-06 ◽

2009 ◽

Vol 1204 ◽

Author(s):

Letian Lin ◽

Lu-Chang Qin ◽

Sean Washburn ◽

Scott Paulson

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Vapor Deposition ◽

Electrical Resistance ◽

Room Temperature ◽

Chemical Vapor ◽

Single Wall Carbon ◽

Transmission Electron ◽

Highly Sensitive

AbstractThe properties of a carbon nanotube (CNT), in particular a single-wall carbon nanotube (SWNT), are highly sensitive to the atomic structure of the nanotube described by its chirality (chiral indices). We have grown isolated SWNTs on a silicon substrate using chemical vapor deposition (CVD) and patterned sub-micron probes using electron beam lithography. The SWNT was exposed by etching the underlying substrate for transmission electron microscope (TEM) imaging and diffraction studies. For each individual SWNT, its electrical resistance was measured by the four-probe method at room temperature and the chiral indices of the same SWNT were determined by nano-beam electron diffraction. The contact resistances were reduced by annealing to typically 3-5 kΩ. We have measured the I-V curve and determined the chiral indices of each nanotube individually from four SWNTs selected randomly – two are metallic and two are semiconducting. We will present the electrical resistances in correlation with the carbon nanotube diameter as well as the band gap calculated from the determined chiral indices for the semiconducting carbon nanotubes. These experimental results are also discussed in connection with theoretical estimations.

Photoconductivity Study of Modified Single-Wall Carbon Nanotube/ Oxotitanium Phthalocyanine

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.631 ◽

2007 ◽

Vol 121-123 ◽

pp. 631-636

Author(s):

T. Li ◽

X.B. Zhang ◽

Y. Li ◽

W.Z. Huang ◽

X.Y. Tao ◽

...

Keyword(s):

Carbon Nanotubes ◽

Charge Transfer ◽

Carbon Nanotube ◽

Chemical Modification ◽

Charge Generation ◽

Photoinduced Charge Transfer ◽

Single Wall Carbon ◽

Discharge Method ◽

Photoinduced Charge

Single-wall Carbon nanotubes (SWNTs) bonded with dodecylamine groups were obtained by chemical modification. The modified SWNTs showed improved solubility in organic solvents. Both its chemical and aggregated structure was characterized by means of FTIR and TEM. The photoconductivity of oxotitanium phthalocyanine (TiOPc) doped with the modified SWNTs was investigated by xerographic photoinduced discharge method. The results showed that the photosensitivity of the double-layered photoreceptor composed of the SWNTs/TiOPc composite as charge generation material was higher than that of pristine TiOPc, and the sensitivity increased with the content of modified SWNTs in the composites. It is the photoinduced charge transfer between TiOPc and SWNTs that contributes to the improved photosensitivity of the modified SWNTs/TiOPc composites.

Apparent Enhanced Solubility of Single-Wall Carbon Nanotubes in a Deuterated Acid Mixture

Research Letters in Nanotechnology ◽

10.1155/2008/296928 ◽

2008 ◽

Vol 2008 ◽

pp. 1-4 ◽

Cited By ~ 6

Author(s):

T. Ramanathan ◽

Frank T. Fisher ◽

Rodney S. Ruoff ◽

L. Catherine Brinson

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Underlying Mechanism ◽

Acid Mixture ◽

Single Wall Carbon ◽

Mixture Treatment ◽

Carbon Nanotube Dispersion ◽

Enhanced Solubility ◽

Nanotube Dispersion

An apparent enhanced solubility of single-wall carbon nanotubes (SWNTs) in the deuterated form of the standard 3 : 1 sulfuric (H2SO4) to nitric (HNO3) acid mixture treatment is reported and attributed to the stronger interaction of deuterium bonds with the single-wall carbon nanotube surface. UV-Visible spectroscopy was used to characterize the apparent enhanced solubility of the SWNTs treated in deuterated forms of the acid mixture in comparison to the standard acid mix, while FTIR was used to analyze the nature of the functional groups generated on the SWNTs as a result of the different acid treatments. The apparent enhanced solubility reported here is consistent with the limited number of computational and experimental results published in the literature regarding the interaction of carbon nanotubes with deuterated solvents; however, a detailed understanding of the underlying mechanism responsible for this observation is currently lacking. The apparent increased solubility observed here could potentially be utilized in many applications where carbon nanotube dispersion is required.