Negatively-Doped Single-Walled Carbon Nanotubes Decorated with Carbon Dots for Highly Selective NO2 Detection

In this study, we demonstrated a highly selective chemiresistive-type NO2 gas sensor using facilely prepared carbon dot (CD)-decorated single-walled carbon nanotubes (SWCNTs). The CD-decorated SWCNT suspension was characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-visible spectroscopy, and then spread onto an SiO2/Si substrate by a simple and cost-effective spray-printing method. Interestingly, the resistance of our sensor increased upon exposure to NO2 gas, which was contrary to findings previously reported for SWCNT-based NO2 gas sensors. This is because SWCNTs are strongly doped by the electron-rich CDs to change the polarity from p-type to n-type. In addition, the CDs to SWCNTs ratio in the active suspension was critical in determining the response values of gas sensors; here, the 2:1 device showed the highest value of 42.0% in a sensing test using 4.5 ppm NO2 gas. Furthermore, the sensor selectively responded to NO2 gas (response ~15%), and to other gases very faintly (NO, response ~1%) or not at all (CO, C6H6, and C7H8). We propose a reasonable mechanism of the CD-decorated SWCNT-based sensor for NO2 sensing, and expect that our results can be combined with those of other researches to improve various device performances, as well as for NO2 sensor applications.

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The High Thickness Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1607 ◽

2010 ◽

Vol 148-149 ◽

pp. 1607-1610

Author(s):

Wei Xue Li ◽

Dun Dong Wang ◽

Hui Jin ◽

Jian Feng Dai ◽

Qing Wang

Keyword(s):

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Deposition Process ◽

X Ray Diffraction ◽

Electroless Coating ◽

Single Walled Carbon ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

20 Nm ◽

Walled Carbon Nanotubes

The Single-walled carbon nanotubes were coated with Ni-P layers by an electroless plating technique. A Ni-P layers are thick and smooth and on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The Single-walled carbon nanotubes were obtained in the suspension of purification solution. The samples have been characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscopy and energy dispersive spectrometry.The coating layers after heat-treatment convert the amorphous Ni-P coated layers into the nanocrystalline Ni-P layers.

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Solution-phase p-type doping of highly enriched semiconducting single-walled carbon nanotubes for thermoelectric thin films

Applied Physics Letters ◽

10.1063/5.0055837 ◽

2021 ◽

Vol 119 (2) ◽

pp. 023302

Author(s):

Noah J. Stanton ◽

Rachelle Ihly ◽

Brenna Norton-Baker ◽

Andrew J. Ferguson ◽

Jeffrey L. Blackburn

Keyword(s):

Thin Films ◽

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Solution Phase ◽

Single Walled Carbon ◽

Thermoelectric Thin Films ◽

P Type ◽

Walled Carbon Nanotubes

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Metal Coated Functionalized Single-Walled Carbon Nanotubes for Composites Application

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.655 ◽

2007 ◽

Vol 561-565 ◽

pp. 655-658 ◽

Cited By ~ 3

Author(s):

Qiang Zeng ◽

Jennifer Luna ◽

Y. Bayazitoglu ◽

Kenneth Wilson ◽

M. Ashraf Imam ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Metal Composite ◽

X Ray ◽

Single Walled Carbon ◽

Transmission Electron ◽

Nucleation Sites ◽

Metal Composite Materials ◽

Walled Carbon Nanotubes

This study is considered as a method for producing multifunctional metal composite materials by using Single-walled Carbon Nanotubes (SWNTs). In this research, various metals (Ni, Cu, Ag ) were successfully deposited onto the surface of SWNTs. It has been found that homogenous dispersion and dense nucleation sites are the necessary conditions to form uniform coating on SWNTs. Functionalization has been applied to achieve considerable improvement in the dispersion of purified single-walled carbon nanotubes. A three-step electroless plating approach was used and the coating mechanism is described in the paper. The samples were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDX). The application of coated SWNTs in Titanium will be discussed in this paper.

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Image Restoration of One-Dimensional HgTe Crystals Formed within Single Walled Carbon Nanotubes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.1131 ◽

2006 ◽

Vol 514-516 ◽

pp. 1131-1134

Author(s):

Jeremy Sloan ◽

Robin Carter ◽

Angus I. Kirkland ◽

Rüdiger R. Meyer ◽

Alexis Vlandas ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Three Dimensional ◽

Single Walled Carbon Nanotubes ◽

One Dimensional ◽

Single Walled Carbon ◽

Semiconductor Crystals ◽

Transmission Electron ◽

Walled Carbon Nanotubes ◽

Separate Crystal

Restored high resolution transmission electron microscopy (HRTEM) images have been recorded from 1D semiconductor crystals formed within narrow diameter (ca. 1.4 nm) single walled carbon nanotubes (SWNTs). Two unique projections were obtained from separate crystal fragments encapsulated within separate nanotubes that has facilitated the reconstruction of the three dimensional arrangement of atoms within the two encapsulated fragments.

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Preparation of Single-Walled Carbon Nanotubes from Starch by Arc Discharge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.454.63 ◽

2012 ◽

Vol 454 ◽

pp. 63-66

Author(s):

Xia Yuan ◽

Yu Liang An ◽

Chen Zhang ◽

Hong Chao Sui

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Scanning Electron Microscopy ◽

Arc Discharge ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Transmission Electron ◽

Walled Carbon Nanotubes ◽

Discharge Method ◽

Scanning Electron

Single-walled carbon nanotubes (SWNTs) have been successfully prepared from starch by arc discharge technique. The SWNTs products were characterized by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The growth mechanism of the SWNTs was discussed in terms of the starch. The results demonstrate that starch is one of the suitable precursor for making SWNTs by arc discharge method.

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NO2 Gas Sensors Based on Individual Suspended Single-Walled Carbon Nanotubes

TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference ◽

10.1109/sensor.2007.4300692 ◽

2007 ◽

Cited By ~ 2

Author(s):

T. Helbling ◽

L. Durrer ◽

R. Pohle ◽

C. Stampfer ◽

A. Goyal ◽

...

Keyword(s):

Carbon Nanotubes ◽

Gas Sensors ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

No2 Gas Sensors ◽

Walled Carbon Nanotubes

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METHODS FOR DISPERSION AND ALIGNMENT OF SINGLE-WALLED CARBON NANOTUBES AND EFFECTS ON THEIR STRUCTURAL AND ELECTRONIC PROPERTIES

International Journal of Nanoscience ◽

10.1142/s0219581x06004553 ◽

2006 ◽

Vol 05 (04n05) ◽

pp. 407-411

Author(s):

JUN JIAO ◽

LIFENG DONG ◽

VACHARA CHIRAYOS ◽

JOCELYN BUSH ◽

JAMES HEDBERG

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Sodium Dodecyl ◽

Single Walled Carbon Nanotubes ◽

Dielectric Medium ◽

High Yield ◽

Single Walled Carbon ◽

Transmission Electron ◽

The Individual ◽

Walled Carbon Nanotubes

Two effective methods for dispersion and alignment of single-walled carbon nanotubes (SWCNTs) were developed. One is the floating-potential dielectrophoresis (FPD) method, which can achieve the alignment of individual SWCNTs between two electrodes with high yield (more than 30%) and high repeatability. The second is the gas blow method. Using the shear forces associated with a rapidly moving fluid, SWCNTs were positioned in a direction corresponding to the flow vector of the fluid. This technique shows great potential for scaling up the displacement of SWCNTs with controlled orientations. Various dispersion agents including ethanol, dichlorobenzene, sodium dodecyl sulfate (SDS) and DNA were investigated with these two methods. It was found that SDS was the most effective dielectric medium used for FPD dispersion and alignment of SWCNTs. The result of electric measurement for the individual SWCNTs aligned between two electrodes suggests that, using the FPD method, both metallic and semiconducting SWCNTs could be aligned between the electrodes. The individual SWCNT resistances measured range from 20 KΩ to 5 MΩ suggesting a high contact resistance between an aligned SWCNT and metal electrodes. High resolution transmission electron microscopy (TEM) and scanning electron microscopy (SEM) characterization reveal DNA molecules wrapped around the SWNCTs after the dispersion process which may affect the intrinsic properties of SWCNTs.

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Functionalization of single-walled carbon nanotubes: Chemistry and characterization

10.1093/oxfordhb/9780199533046.013.16 ◽

2017 ◽

Author(s):

R. Graupner ◽

F. Hauke

Keyword(s):

Carbon Nanotubes ◽

Nir Spectroscopy ◽

Single Walled Carbon Nanotubes ◽

Covalent Attachment ◽

Spectroscopic Techniques ◽

Force Microscopy ◽

Single Walled Carbon ◽

Transmission Electron ◽

Tunnelling Microscopy ◽

Walled Carbon Nanotubes

This article examines the chemical functionalization and structural alteration of single-walled carbon nanotubes (SWCNTs). It describes the covalent functionalization of the SWCNT framework that is the covalent attachment of functional entities onto the CNT scaffold. In particular, it considers the chemical modification and reactivity of SWCNTs in the context of the reactivity of graphite and fullerenes. It also discusses the defect and sidewall functionalization of SWCNTs, along with various techniques used in the characterization ofSWCNTs upon functionalization, namely: thermogravimetric analysis, spectroscopic techniques such as UV-Vis-NIR spectroscopy and Raman spectroscopy, and microscopic techniques like transmission electron microscopy, atomic force microscopy and scanning tunnelling microscopy.

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Antimony Selenide Crystals Encapsulated within Single Walled Carbon Nanotubes-A DFT Study

E-Journal of Chemistry ◽

10.1155/2009/837807 ◽

2009 ◽

Vol 6 (s1) ◽

pp. S147-S152 ◽

Cited By ~ 5

Author(s):

Navaratnarajah Kuganathan

Keyword(s):

Carbon Nanotubes ◽

Binding Energy ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Single Walled Carbon Nanotubes ◽

Binding Energies ◽

Single Walled Carbon ◽

Transmission Electron ◽

Antimony Selenide ◽

Walled Carbon Nanotubes

The structure and binding energies of antimony selenide crystals encapsulated within single-walled carbon nanotubes are studied using density functional theory. Calculations were performed on the simulated Sb2Se3structure encapsulated within single walled nanotube to investigate the perturbations on the Sb2Se3crystal and tube structure and electronic structure and to estimate the binding energy. The calculated structures are in good agreement with the experimental high resolution transmission electron microscopy images of the Sb2Se3@SWNT. The calculated binding energy shows that larger diameter tube could accommodate the Sb2Se3crystals exothermically. Minimal charge transfer is observed between nanotube and the Sb2Se3crystals.

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