Dry and Direct Deposition of Aerosol-Synthesized Single-Walled Carbon Nanotubes by Thermophoresis

Author(s)
Patrik Laiho, Kimmo Mustonen, Yutaka Ohno, Shigeo Maruyama, Esko I. Kauppinen
Abstract

Single-walled carbon nanotubes (SWCNTs) show great potential as an active material in electronic and photonic devices, but their applicability is currently limited by shortcomings in existing deposition methods. SWCNTs can be dispersed from liquid solutions; however, their poor solubility requires the use of surfactants and ultrasonication, causing defects and degradation in device performance. Likewise, the high temperatures required by their chemical vapor deposition growth limit substrates on which SWCNTs can be directly grown. Here, we present a systematic study of the direct deposition of pristine, aerosol-synthesized SWCNTs by thermophoresis. The density of the deposited nanotube film can be continuously adjusted from individual, separated nanotubes to multilayer thin films by changing the deposition time. Depending on the lateral flow inside the thermophoretic precipitator, the angular distribution of the deposited SWCNT film can be changed from uniform to nonuniform. Because the substrate is kept at nearly ambient temperature, deposition can be thus carried out on practically any flat substrate with high efficiencies close to unity. The thermophoretic terminal velocity of SWCNTs, determined by aerosol loss measurements, is found to be approximately one-third of the usual prediction in the free molecular regime and shows a weak dependence on the nanotube diameter. As a demonstration of the applicability of our technique, we have used thermophoretic deposition in the fabrication of carbon nanotube thin-film transistors with uniform electrical properties and a high, over 99.5%, yield.

Organisation(s)
Physics of Nanostructured Materials
Journal
ACS Applied Materials and Interfaces
Volume
9
Pages
20738-20747
No. of pages
10
ISSN
1944-8244
DOI
https://doi.org/10.1021/acsami.7b03151
Publication date
06-2017
Publication status
Published
Peer reviewed
Yes
Austrian Fields of Science 2012
210004 Nanomaterials, 103018 Materials physics
Keywords
Aerosol technology, aerosol deposition, thermophoresis, single-walled carbon nanotubes, floating-catalyst chemical vapor deposition, thin-film transistors, HIGH-PERFORMANCE ELECTRONICS, BOUNDARY-LAYER, PARTICLES, TRANSISTORS, TRANSPORT, NETWORKS, ARRAYS, NANOPARTICLES, GROWTH, FILMS
Portal url
https://ucris.univie.ac.at/portal/en/publications/dry-and-direct-deposition-of-aerosolsynthesized-singlewalled-carbon-nanotubes-by-thermophoresis(03dbd486-b76e-4abb-93f4-48b13cf6fa81).html