Cylindrical Metal Wire Surface Coating with Multiwalled Carbon Nanotubes by an Atmospheric-Pressure Microplasma CVD Technique

Abstract

A simple technique to coat the surface of a cylindrical tungsten wire with multiwalled (MW) carbon nanotubes (CNTs) has been developed. The coating was deposited by CVD using an atmospheric-pressure microplasma generated in a quartz capillary by a few tens of watts of UHF power. The deposition and growth manner of the MWCNTs were controlled by the method of passage of CH 4 and vaporized ferrocene gases. When the two gases were supplied simultaneously, the deposited surface of the tungsten wire contained tangles of MWCNTs. However, aligned MWCNTs were formed when vaporized ferrocene was fed first followed by CH 4 . In this process, the growth rate of MWCNTs was relatively high compared with conventional plasma-enhanced CVD. This is a new method to prepare MWCNTs efficiently with low energy (few tens of watts) and minimum time.

Nanoscience with non-equilibrium plasmas at atmospheric pressure

“…Microplasma jets can be created by any excitation mode (dc [68], rf [45], microwave [46,47]). They can be processed directly or in a remote mode, continuously or in a pulsed regime.…”

“…In that sense, any reactive plasma used as a source of nanoparticles plays the same role. One of the most explicit examples based on this idea was first proposed by Ito and Terashima [69] and by Shimizu et al during the following years [46,47,[70][71][72]. The microplasma generator consists of a capillary (100-500 µm inner diameter) made of quartz or alumina [72] joined to a metal tube where the gases are injected, and a tungsten wire (50 µm in diameter) inserted into the capillary.…”

“…Matter gets organized spontaneously on the substrate and, under the effect of the plasma, produces architectures of nanometric objects. In the second approach, the possibility to grow an isolated nanometric object from atmospheric plasmas and eventually to assemble several of these elementary units into given architectures was described by several groups [44][45][46][47], with modest, yet undeniable, success. To date, all the achievements made with this second approach are micrometric, but recent developments on plasmas in or on liquids [48] suggest that it would be possible to reach the nanometre scale.…”

Gas temperature and electron temperature measurements by emission spectroscopy for an atmospheric microplasma

“…1,2 Nevertheless only in the last decade researchers have increasingly studied microscale plasma in a wider sense, probably due to a growing belief in the potential applications. 3,4 Microplasmas are now being considered in many and different fields including material processing, [5][6][7][8][9][10][11][12][13][14][15] gas treatment, 16 light sources, 17 propulsion, 18 analytical chemistry, [19][20][21][22][23][24] photonics, 25,26 and medical applications. 27,28 Moreover the basic scientific interest is growing stronger as microplasma characteristics are unfolded and recognized to be different from the larger parents.…”

Perspectives on atmospheric-pressure plasmas for nanofabrication

“…Direct evaporation, sputtering or etching of solid materials is an alternative approach that has been explored via atmospheric-pressure microplasma synthesis [16,[53][54][55][56][57][58][59][60][61][62][63][64]. A critical challenge for this method is how to control the mechanism for particle nucleation and growth which depends on many factors including the evaporation rate of the solid metal source.…”