Effect of interaction between AC electric field and phonon oscillation of metal cluster on tip-growth of carbon nanotube

Dispersed aligned single-wall carbon nanotube (SWCNT) array has been formed between electrodes by electric field assisted alignment of surface decorated SWCNTs. The surface decoration of SWCNTs with functional molecules allows them to dispersedly bridge metal electrodes and effectively obviates the entanglement between SWCNTs. The influences of solution volatility and electric-field type on the alignment are investigated. It is indicated that the well-oriented SWCNT array can be achieved by using the high-volatility solvent and the high-frequency AC electric field to align SWCNTs.

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Linear aggregation of spherical nanogolds in carbon nanotube suspension under influence of AC electric field

Journal of Physics Conference Series ◽

10.1088/1742-6596/1380/1/012010 ◽

2019 ◽

Vol 1380 ◽

pp. 012010

Author(s):

Rung Mungkhong ◽

Nattaporn Chattham ◽

Apichart Pattanaporkratana

Keyword(s):

Carbon Nanotube ◽

Electric Field ◽

Ac Electric Field ◽

Linear Aggregation

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Phenomenological Characterization of the Fabrication of Aligned Carbon Nanotube Nanocomposites via Dielectrophoresis Under AC Electric Field

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference ◽

10.2514/6.2013-1582 ◽

2013 ◽

Author(s):

Engin C. Sengezer ◽

Gary D. Seidel

Keyword(s):

Carbon Nanotube ◽

Electric Field ◽

Ac Electric Field

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Integration of Single Multi-Walled Carbon Nanotube on Micro Systems

Microelectromechanical Systems ◽

10.1115/imece2002-33325 ◽

2002 ◽

Cited By ~ 2

Author(s):

Jaehyun Chung ◽

Junghoon Lee ◽

Rodney S. Ruoff ◽

Wing Kam Liu

Keyword(s):

Carbon Nanotube ◽

Electric Field ◽

Frequency Component ◽

Metal Electrodes ◽

New Techniques ◽

Ac Electric Field ◽

Multi Walled Carbon Nanotube ◽

Assembly Technique ◽

Dc Component ◽

Micro Systems

This paper presents new techniques for depositing single multi-walled carbon nanotube (MWCNT) on metal electrodes based on micro-fabrication and an electric-field-guided assembly technique. It was demonstrated that a single MWCNT can be directionally deposited across a microscale gap guided by a biased AC electric field. The biased AC method could effectively avoid the deposition of undesirable particles, and yet maintained highly ordered deposition results. A specific AC frequency component was applied to attract only desired CNTs into a gap and a DC component was used to diminish electric field significantly when the first CNT is deposited. This method can be easily combined with other micromachining process and possibly applied to batch production.

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Alignment of MWCNTs in Polymer Composites by Dielectrophoresis

ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer, Parts A and B ◽

10.1115/mnht2008-52160 ◽

2008 ◽

Author(s):

Ming-Wen Wang

Keyword(s):

Mechanical Properties ◽

Carbon Nanotube ◽

Electric Field ◽

Polymer Composites ◽

Flexural Modulus ◽

Low Carbon ◽

Multi Wall Carbon Nanotubes ◽

Structural Reinforcement ◽

Ac Electric Field

Successful structural reinforcement of polymer matrices by carbon nanotube has been shown where significant improvement of mechanical properties was achieved at very low carbon nanotube loading. Due to the mechanical properties of aligned composites is better than random has been demonstrated; the conception is not easy to perform in carbon nanotube polymer composites via conventional techniques. Here, we report a novel operation to actively align and network multi-wall carbon nanotubes (MWCNTs) in a polymer matrix. In this process, MWCNTs were aligned via AC electric field induced dipolar interactions among the nanotubes in a viscous matrix followed by immobilization by curing polymerization under continued application of the anisotropic electric field. In situ SEM verified the electrostatic stabilization of the MWCNTs in the dispersion and the orientation and agglomeration caused by the dielectrophoretic force. Alignment of MWCNTs was controlled as a function of magnitude, frequency, and application time of the applied dielectrophoresis. In the present work, MWCNTs are not only aligned along the field, but also migrate laterally to form thick. The actively aligned MWCNTs amplify the flexural modulus and wear-resisting property.

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AC Electric Field-Induced Alignment and Long-Range Assembly of Multi-Wall Carbon Nanotubes Inside Aqueous Media

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.871 ◽

2007 ◽

Vol 7 (12) ◽

pp. 4322-4332 ◽

Cited By ~ 8

Author(s):

Zhihui Guo ◽

Jeffery A. Wood ◽

Krista L. Huszarik ◽

Xiaohu Yan ◽

Aristides Docoslis

Keyword(s):

Carbon Nanotubes ◽

Electrical Resistivity ◽

Carbon Nanotube ◽

Electric Field ◽

Long Range ◽

Applied Voltage ◽

Three Dimensional ◽

Field Frequency ◽

Ac Electric Field ◽

Ac Field

The present work examines the behavior of multiwall carbon nanotubes (MWCNT) inside AC electric fields created by three-dimensional electrodes. The response of carbon nanotubes stably suspended in water with the aid of a nonionic surfactant is monitored by combining microscopic observations with on-line measurements of the suspension resistivity. It is found that polarization effects induced by the externally applied AC electric field on MWCNTs can cause their unidirectional orientation and end-to-end contact that result in formations of spatially distributed, long-range, three-dimensional and electrically conducting structures that span the entire gap between the electrodes. The length of the formed structures, which in the present case was approximately 30 times larger than that of an individual carbon nanotube, can be controlled by adjusting the spacing between the electrodes. The influence of main experimental parameters, namely, MWCNT concentration, applied voltage, AC field frequency, and electrode surface topography on the suspension behavior is experimentally examined. Results are demonstrated for applied voltage values, AC field frequencies, and carbon nanotube concentrations in the range 4–40 Vptp, 10 Hz–5 MHz, and 0.001–2.0 wt%, respectively. While higher electric field strengths accelerate the formation of aligned structures, higher frequency values were found to result in suspensions that exhibit smaller electrical resistivity. Carbon nanotube dispersions exposed to an AC electric field exhibit a 100-fold or more decrease in their electrical resistivity, even when carbon nanotube concentrations as low as 0.005 wt% are used.

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Optically Induced Field-Emission Source Based on Aligned Vertical Carbon Nanotube Arrays

Nanomaterials ◽

10.3390/nano11071810 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1810

Author(s):

Mengjie Li ◽

Qilong Wang ◽

Ji Xu ◽

Jian Zhang ◽

Zhiyang Qi ◽

...

Keyword(s):

Carbon Nanotube ◽

Electric Field ◽

Field Emission ◽

Field Enhancement ◽

Absorption Efficiency ◽

Photon Absorption ◽

Nanotube Arrays ◽

Carbon Nanotube Arrays ◽

Induced Field ◽

Optically Induced

Due to the high field enhancement factor and photon-absorption efficiency, carbon nanotubes (CNTs) have been widely used in optically induced field-emission as a cathode. Here, we report vertical carbon nanotube arrays (VCNTAs) that performed as high-density electron sources. A combination of high applied electric field and laser illumination made it possible to modulate the emission with laser pulses. When the bias electric field and laser power density increased, the emission process is sensitive to a power law of the laser intensity, which supports the emission mechanism of optically induced field emission followed by over-the-barrier emission. Furthermore, we determine a polarization dependence that exhibits a cosine behavior, which verifies the high possibility of optically induced field emission.

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