Ultra-high-yield growth of vertical single-walled carbon nanotubes: Hidden roles of hydrogen and oxygen.

Proc Natl Acad Sci U S A

Department of Chemistry and Laboratory for Advanced Materials and Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA.

Published: November 2005

An oxygen-assisted hydrocarbon chemical vapor deposition method is developed to afford large-scale, highly reproducible, ultra-high-yield growth of vertical single-walled carbon nanotubes (V-SWNTs). It is revealed that reactive hydrogen species, inevitable in hydrocarbon-based growth, are damaging to the formation of sp(2)-like SWNTs in a diameter-dependent manner. 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 V-SWNT films on any substrate, lifting a major substrate-type limitation for aligned SWNTs.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1283442PMC
http://dx.doi.org/10.1073/pnas.0507064102DOI Listing

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