Influence of electric field and emission current on the configuration of nanotubes in carbon nanotube layers

Киселев, Н.А.; Musatov, A. L.; Kukovitskii, E. F.; Hutchison, J. L.; Жигалина, О. М.; Артемов, В. В.; Grigoriev, Yu. V.; Izrael’yants, K. R.; L’vov, S.G.

doi:10.1016/j.carbon.2005.06.029

Cited by 17 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Redistribution subject to ECS terms of use (see 132.174.254.155 Downloaded on 2015-04-05 to IP field emission properties, Raman and XRD spectra of such nanotube structures as well as external morphology and internal microstructure of individual carbon nanotubes were previously investigated in works. 8,30,31 Produced carbon nanotube cold cathodes (Fig. 11) were installed into small-sized X-ray tube and have demonstrated stable characteristics of the emitter current in the direct current mode.…”

Section: Discussionmentioning

confidence: 99%

Increased Carbon Chemical Vapor Deposition and Carbon Nanotube Growth on Metal Substrates in Confined Spaces

Kukovitsky

L’vov

2012

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Experimental study of carbon deposition and carbon nanotube growth between stacked metallic substrates was conducted. The batch chemical vapor deposition (CVD) reactor was used with polyethylene as the carbon precursor. Increased carbon deposition was established on surfaces between stacked nickel substrates as compared to surfaces facing to open spaces. In general case carbon films deposited between substrates were not uniform giving rise to complicated profiles. The simple diffusion-reaction scheme gives carbon film thickness profiles closely resembling those experimentally observed. This similarity is considered as evidence of homogeneous-heterogeneous reaction sequences proceeding in narrow gap between catalytically active surfaces. Increased carbon nanotube growth was believed to occur as a result of the involvement of hydrocarbon radicals generated by the catalyst surface with subsequent release into the gas phase. Radicals accelerate gas-phase reactions providing reactive intermediates. Ultimately catalytic gas phase activation in the confined space promotes increased carbon formation. An explanation of the experimental results is proposed and a practical application was demonstrated.Carbon films and layers on supporting substrates are perspective components for an increasing number of potential applications. Chemical vapor deposition (CVD) is the preferred method to produce carbon films on substrates. For carbon materials obtained by CVD process carbon species and their properties are determined by the interacting influences of hydrodynamics and chemical kinetics, which in turn depend on the reactor type, process conditions (chemical precursor, temperature, temperature gradients, pressure), surface catalytic properties and may be affected also by extrinsic factors as gas or surface impurities, surface configuration and surface morphology. The vast majority of experimental works to produce carbon films or layers has been made using the crystalline silicon as a substrate. In particular, carbon nanotubes (CNT) are frequently being synthesized on silicon with coated catalyst (Ni, Fe, Co and alloys). This is commonly justified by the need for compatibility with technologies of modern microelectronics. There exist, however, many applications for which the use of metallic substrates is preferable to other materials or essential for device performance. The considerable effort has been devoted to the synthesis of CVD diamond films on metal substrates at low temperatures and pressures. 1-3 Such films have great potential for applications in microelectronic devices, as tools, heat sinks, hard coatings, corrosion and wear resistant surfaces. CVD techniques for producing diamond films require a means of activating gas-phase carbon-containing precursor molecules. Thermal or plasma activation procedures generate hydrogen and hydrocarbon radicals which participate in surface chemical reactions resulting in film growth. In fact, the same procedures are now widely used in nanotube CVD processes to low synthesis temperature...

show abstract

Section: Discussionmentioning

confidence: 99%

Increased Carbon Chemical Vapor Deposition and Carbon Nanotube Growth on Metal Substrates in Confined Spaces

Kukovitsky

L’vov

2012

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…In addition, open edges of graphene layers were observed on both the inner and outer surface of the hollow tube (marked with black arrows), as expected from a CSCNT structure. 28 The existence of the incline angle may be explained by the relatively high content of hydrogen in the growth process. Hydrogen was assumed to enable the cup-stacked structure with open edges of graphene layers since it satisfies the valences at the cone edges.…”

Section: Experimental Methodsmentioning

confidence: 99%

Reinforced Carbon Nanotubes as Electrically Conducting and Flexible Films for Space Applications

Atar

Grossman²,

Gouzman³

et al. 2014

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Chemical vapor deposition (CVD)-grown entangled carbon nanotube (CNT) sheets are characterized by high electrical conductivity and durability to bending and folding. However, since freestanding CNT sheets are mechanically weak, they cannot be used as stand-alone flexible films. In this work, polyimide (PI) infiltration into entangled cup-stacked CNT (CSCNT) sheets was studied to form electrically conducting, robust, and flexible films for space applications. The infiltration process preserved CNTs' advantageous properties (i.e., conductivity and flexibility), prevented CNT agglomeration, and enabled CNT patterning. In particular, the CNT-PI films exhibited ohmic electrical conductance in both the lateral and vertical directions, with a sheet resistivity as low as 122 Ω/□, similar to that of as-grown CNT sheets, with minimal effect of the insulating matrix. Moreover, this high conductivity was preserved under mechanical and thermal manipulations. These properties make the reported CNT-PI films excellent candidates for applications where flexibility, thermal stability, and electrical conductivity are required. Particularly, the developed CNT-PI films were found to be durable in space environment hazards such as high vacuum, thermal cycling, and ionizing radiation, and hence they are suggested as an alternative for the electrostatic discharge (ESD) protection layer in spacecraft thermal blankets.

show abstract

“…As seen from Figure 2, the emitter consists of a multitude of interlaced carbon nanotubes. Special experiments that were performed on similar emitters (5) showed that at the high electric field that corresponded to the appearance of field electron emission, nanotubes stretched towards the anode and thus became partially oriented. The investigation of carbon nanotube structure in similar emitter fulfilled by the transmission electron microscopy method showed that emitter consisted of nanotubes 10-50 nm in diameter and about 10 µm in length (5,6).…”

Section: Construction Of the X-ray Tube And Fabrication Of The Field mentioning

confidence: 99%

Properties of Field Electron Emitter Based on Carbon Nanotubes Installed in the Small-Sized X-Ray Tube

Musatov

Gulyaev

Izrael’yants

et al. 2010

Fullerenes, Nanotubes and Carbon Nanostructures

View full text Add to dashboard Cite

A small-sized X-ray tube with a carbon nanotube planar field electron emitter has been manufactured and tested. Field electron emitter was grown by the chemical vapor deposition (CVD) method on a nickel substrate. During long time tests (more than 50 hours) the X-ray tube has demonstrated stable characteristics of the emitter current in the dc mode. Relative emission current fluctuations were about 0.3% at the emitter emission current equal to 550 µA.

show abstract

Influence of electric field and emission current on the configuration of nanotubes in carbon nanotube layers

Cited by 17 publications

References 21 publications

Increased Carbon Chemical Vapor Deposition and Carbon Nanotube Growth on Metal Substrates in Confined Spaces

Increased Carbon Chemical Vapor Deposition and Carbon Nanotube Growth on Metal Substrates in Confined Spaces

Reinforced Carbon Nanotubes as Electrically Conducting and Flexible Films for Space Applications

Properties of Field Electron Emitter Based on Carbon Nanotubes Installed in the Small-Sized X-Ray Tube

Contact Info

Product

Resources

About