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Ultra-High Yield Growth of Vertical Single-Walled Carbon Nanotubes: Hidden Roles of Hydrogen and Oxygen

Guangyu Zhang·David Mann·Li Zhang·Ali Javey·Yiming Li·Erhan Yenilmez·Qian Wang·James McVittie·Yoshio Nishi·James Gibbons·Hongjie Dai
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Abstract

An oxygen assisted hydrocarbon chemical vapor deposition (CVD) method is developed to afford large-scale highly reproducible ultra high-yield growth of vertical single-walled carbon nanotubes (SWNT). It is revealed that reactive hydrogen (H)-species, inevitable in hydrocarbon-based growth, are damaging to the formation of sp2-like SWNTs. The addition of oxygen scavenges H-species and provides a powerful control over the C/H ratio to favor SWNT growth. The revelation of the roles played by hydrogen and oxygen leads to a unified and universal optimum growth condition for SWNTs. Further, a versatile method is developed to form vertical SWNT films on any substrate, lifting a major substrate-type limitation for aligned SWNTs.

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Guangyu Zhang, David Mann, Li Zhang, Ali Javey, Yiming Li, Erhan Yenilmez, Qian Wang, James McVittie, Yoshio Nishi, James Gibbons, Hongjie Dai. 2005-11-01. Ultra-High Yield Growth of Vertical Single-Walled Carbon Nanotubes: Hidden Roles of Hydrogen and Oxygen. https://doi.org/10.1073/pnas.0507064102

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