Abstract
We report on the poisoning of tungsten filaments during the hot-filament chemical vapour deposition process at typical carbon nanotube (CNT) deposition conditions and filament temperatures ranging from 1400 to 2000 °C. The morphological and structural changes of the filaments were investigated using scanning electron microscopy and X-ray diffraction, respectively. Our results conclusively show that the W-filament is not stable during the carburization process and that both mono- and ditungsten-carbides form within the first 5 min. Cracks and graphitic microspheres form on the carbide layer during the first 15 min at the temperatures ≥1600 °C. The microspheres subsequently coalesce to form a graphite layer, encapsulating a fully carburized filament at the temperature of 2000 °C after 60 min, which inhibits the catalytic activity of the filament to produce atomic hydrogen. The structural changes of the filament also induce variations in its temperature, illustrating the instability of the filament during the deposition of CNTs.
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References
Moustakas TD (1989) Solid State Ionics 32–33:861
Park SS, Lee JY (1993) J Mater Sci 28:1799. doi:https://doi.org/10.1007/BF00595748
Sein H, Ahmed W, Hassan U, Ali N, Cracio JJ, Jackson MJ (2002) J Mater Sci 37:5057. doi:https://doi.org/10.1023/A:1021043817134
Fortunato W, Chiquito AJ, Galzerani JC, Moro JR (2007) J Mater Sci 42:7331. doi:https://doi.org/10.1007/s10853-007-1575-0
Rastogi AC, Desu SB (2005) Polymer 46:3440
Filonovich SA, Ribeiro M, Rolo AG, Alpuim P (2008) Thin Solid Films 516:576
Weissenbacher R, Haubner R, Aigner K, Lux B (2002) Diamond Relat Mater 11:191
Pal S, Jacob C (2006) J Mater Sci 41:5429. doi:https://doi.org/10.1007/s10853-006-0270-x
Dillon AC, Mahan AH, Alleman JL, Heben MJ, Parilla PA, Jones KM (2003) Thin Solid Films 430:292
Sommer M, Smith FW (1990) J Mater Res 511:2433
Van der Werf CHM, Van Veenendaal PATT, Van Veen MK, Hardeman AJ, Rusche MYS, Rath JK, Schropp REI (2003) Thin Solid Films 430:46
Roger J, Audubert F, Petitcorps YL (2008) J Mater Sci 43:3938. doi:https://doi.org/10.1007/s10853-007-2334-y
Kromka A, Janίk J, Šatka A, Pavlov J, Červeň I (2001) Acta Physica Slovaca 51:359
Sommer M, Mui K, Smith FW (1989) Solid State Commun 69:775
Schwarz S, Zeiler E, Rosiwal SM, Singer RF (2002) Mater Sci Eng A 335:236
Okoli S, Haubner R, Lux B (1991) Surf Coat Technol 47:585
Matsubara H, Sakuma T (1990) J Mater Sci 25:4472. doi:https://doi.org/10.1007/BF00581110
Davidson CF, Alexander GB, Wadsworth ME (1979) Metall Trans A 10A:1059
Wolden C, Gleason KK (1994) J Appl Phys 62:3102
Arendse CJ, Malgas GF, Scriba MR, Cummings FR, Knoesen D (2007) J Nanosci Nanotechnol 7:3638
International Centre for Diffraction Data (ICDD): W (89-3012), W2C (79-0743), WC (89-2727) and graphite (75-1621)
Vieira SMC, Rego CA, Birkett PR (2008) Diamond Relat Mater 17:100
Hernberg R, Li DM, Mäntylä T (1998) Diamond Relat Mater 7:1709
Langmuir L (1912) J Am Chem Soc 34:1310
Honda S, Katayama M, Lee K, Ikuno T, Ohkura S, Oura K, Furuta H, Hirao T (2003) Jpn J Appl Phys 42:L441
Seo HK, Ansari SG, Kim GS, Kim YS, Shin HS (2004) J Mater Sci 39:5771. doi:https://doi.org/10.1023/B:JMSC.0000040088.09431.e6
Acknowledgements
The authors acknowledge the financial support of the Department of Science and Technology, the National Research Foundation and the Council for Scientific and Industrial Research (Project No. HGERA2S) of South Africa. The authors are especially thankful to Mr. Adrian Josephs (Microscopy Unit, University of the Western Cape) for his assistance with the SEM measurements and sample preparation.
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Oliphant, C.J., Arendse, C.J., Malgas, G.F. et al. Filament poisoning at typical carbon nanotube deposition conditions by hot-filament CVD. J Mater Sci 44, 2610–2616 (2009). https://doi.org/10.1007/s10853-009-3341-y
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DOI: https://doi.org/10.1007/s10853-009-3341-y