Joint effect of ethylene and toluene on carbon nanotube growth

• Published in: Carbon (New York) Vol. 189; pp. 474 - 483
• Main Authors: Khabushev, Eldar M., Krasnikov, Dmitry V., Goldt, Anastasia E., Fedorovskaya, Ekaterina O., Tsapenko, Alexey P., Zhang, Qiang, Kauppinen, Esko I., Kallio, Tanja, Nasibulin, Albert G.
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 15-04-2022; Elsevier BV
• Subjects: Aerosol CVD synthesis; Carbon; Catalysts; Chemical synthesis; Conductivity; Equivalent sheet resistance; Ethylene; Floating catalyst; Nanotubes; Nucleation; Single wall carbon nanotubes; Single-walled carbon nanotube; Toluene; Floating catalyst; Single-walled carbon nanotube; Equivalent sheet resistance; Aerosol CVD synthesis
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2021.12.052

This work contributes to the understanding of single-walled carbon nanotube synthesis by an aerosol CVD method using ethylene and toluene as a hybrid carbon source. We evaluated an extensive set of synthesis conditions revealing the role of ferrocene, toluene, and ethylene. We found the fundamental role of ethylene promoting nanotube nucleation and catalyst activation degree at all the concentrations studied, and enhancing nanotube growth at low ethylene content. We observed the interplay effect of toluene and ethylene concentrations on the nanotube growth rate, accompanied by the detrimental effect of toluene on catalyst activation degree. Nevertheless, toluene apparently promotes nanotube crystallinity, increasing the film conductivity while used as an individual carbon source. Adjusting the ethylene and toluene concentrations, we produced carbon nanotube-based transparent and conductive films with an equivalent sheet resistance (at 90% transmittance at 550 nm wavelength) value of 57 Ω/□ at the synthesis yield of 0.24 cm2 L−1, which is at least two times higher than the results reported earlier.
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•Ethylene boosts SWCNT nucleation and enhances catalyst activation degree.•Ethylene promotes growth rate but deactivates catalyst at high concentrations.•Toluene improves nanotube crystanillity and deteriorates catalyst activation degree.•Toluene and ethylene together yield in better performance unlike separate supply.•High-yield production of high-performance transparent conductive films demonstrated.