X-ray photoelectron spectroscopy study on Fe and Co catalysts during the first stages of ethanol chemical vapor deposition for single-walled carbon nanotube growth
Abstract
Optimized chemical vapor deposition processes for single-walled carbon nanotube (SWCNT) can lead to the growth of dense, vertically aligned, mm-long forests of SWCNTs. Precise control of the growth process is however still difficult, mainly because of poor understanding of the interplay between catalyst, substrate and reaction gas. In this paper we use x-ray photoelectron spectroscopy (XPS) to study the interplay between Fe or Co catalysts, SiO{sub 2} and Al{sub 2}O{sub 3} substrates and ethanol during the first stages of SWCNT forest growth. With XPS we observe that ethanol oxidizes Fe catalysts at carbon nanotube (CNT) growth temperatures, which leads to reduced carbon nanotube growth. Ethanol needs to be decomposed by a hot filament or other technique to create a reducing atmosphere and reactive carbon species in order to grow vertically aligned single-walled carbon nanotubes from Fe catalysts. Furthermore, we show that Al{sub 2}O{sub 3}, unlike SiO{sub 2}, plays an active role in CNT growth using ethanol CVD. From our study we conclude that metallic Fe on Al{sub 2}O{sub 3} is the most optimal catalyst/substrate combination for high-yield SWCNT forest growth, using hot filament CVD with ethanol as the carbon containing gas.
- Authors:
-
- IBM TJ Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598 (United States)
- Publication Date:
- OSTI Identifier:
- 21538177
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Applied Physics
- Additional Journal Information:
- Journal Volume: 109; Journal Issue: 6; Other Information: DOI: 10.1063/1.3552306; (c) 2011 American Institute of Physics; Journal ID: ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 77 NANOSCIENCE AND NANOTECHNOLOGY; ALUMINIUM OXIDES; CARBON; CATALYSTS; CHEMICAL VAPOR DEPOSITION; COBALT; ETHANOL; FABRICATION; FILAMENTS; IRON; MOLECULES; NANOTUBES; PRECURSOR; PROCESSING; SCREENING; SCREENS; SILICON OXIDES; SUBSTRATES; X-RAY PHOTOELECTRON SPECTROSCOPY; ALCOHOLS; ALUMINIUM COMPOUNDS; CHALCOGENIDES; CHEMICAL COATING; DEPOSITION; ELECTRON SPECTROSCOPY; ELEMENTS; HYDROXY COMPOUNDS; METALS; NANOSTRUCTURES; NONMETALS; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; PHOTOELECTRON SPECTROSCOPY; SILICON COMPOUNDS; SPECTROSCOPY; SURFACE COATING; TRANSITION ELEMENTS
Citation Formats
Oida, Satoshi, McFeely, Fenton R, and Bol, Ageeth A. X-ray photoelectron spectroscopy study on Fe and Co catalysts during the first stages of ethanol chemical vapor deposition for single-walled carbon nanotube growth. United States: N. p., 2011.
Web. doi:10.1063/1.3552306.
Oida, Satoshi, McFeely, Fenton R, & Bol, Ageeth A. X-ray photoelectron spectroscopy study on Fe and Co catalysts during the first stages of ethanol chemical vapor deposition for single-walled carbon nanotube growth. United States. https://doi.org/10.1063/1.3552306
Oida, Satoshi, McFeely, Fenton R, and Bol, Ageeth A. 2011.
"X-ray photoelectron spectroscopy study on Fe and Co catalysts during the first stages of ethanol chemical vapor deposition for single-walled carbon nanotube growth". United States. https://doi.org/10.1063/1.3552306.
@article{osti_21538177,
title = {X-ray photoelectron spectroscopy study on Fe and Co catalysts during the first stages of ethanol chemical vapor deposition for single-walled carbon nanotube growth},
author = {Oida, Satoshi and McFeely, Fenton R and Bol, Ageeth A},
abstractNote = {Optimized chemical vapor deposition processes for single-walled carbon nanotube (SWCNT) can lead to the growth of dense, vertically aligned, mm-long forests of SWCNTs. Precise control of the growth process is however still difficult, mainly because of poor understanding of the interplay between catalyst, substrate and reaction gas. In this paper we use x-ray photoelectron spectroscopy (XPS) to study the interplay between Fe or Co catalysts, SiO{sub 2} and Al{sub 2}O{sub 3} substrates and ethanol during the first stages of SWCNT forest growth. With XPS we observe that ethanol oxidizes Fe catalysts at carbon nanotube (CNT) growth temperatures, which leads to reduced carbon nanotube growth. Ethanol needs to be decomposed by a hot filament or other technique to create a reducing atmosphere and reactive carbon species in order to grow vertically aligned single-walled carbon nanotubes from Fe catalysts. Furthermore, we show that Al{sub 2}O{sub 3}, unlike SiO{sub 2}, plays an active role in CNT growth using ethanol CVD. From our study we conclude that metallic Fe on Al{sub 2}O{sub 3} is the most optimal catalyst/substrate combination for high-yield SWCNT forest growth, using hot filament CVD with ethanol as the carbon containing gas.},
doi = {10.1063/1.3552306},
url = {https://www.osti.gov/biblio/21538177},
journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 6,
volume = 109,
place = {United States},
year = {Tue Mar 15 00:00:00 EDT 2011},
month = {Tue Mar 15 00:00:00 EDT 2011}
}