The practical use of single-walled carbon nanotubes (SWNTs) in electronics such as field-effect transistors has been somewhat hindered by the presence of metallic nanotubes in current synthetic methods. Scientists in Singapore and the US have come up with a simple method to convert unwanted metallic single-walled carbon nanotubes (M-SWNTs) into semiconducting ones (S-SWNTs).
The team immersed as synthesised SWNT on-chip devices and immersed them into a solution containing an aromatic compound – 2-ethylanthraquinone (EAQ), which is a mild radical initiator. The EAQ-generated radicals preferentially attack the M-SWNTs over the S-SWNTs in situ, converting them to its semiconducting mode.
Alternative methods for converting M-SWNTs to S-SWNTs use either electron irradiation, which is difficult to scale up, or hydrogen plasma, which is aggressive and can’t be controlled. “This approach (using EAQ…) is simple, mild and easily scalable to whole wafers,” claim John Rogers (University of Illinois at Urbana-Champaign, US) and Mary Chan-Park (Nanyang Technological University, Singapore).
Free access to the full article online:
On-chip diameter-dependent conversion of metallic to semiconducting single-walled carbon nanotubes by immersion in 2-ethylanthraquinone
Jiangbo Li, Xuena Luan, Yinxi Huang, Simon Dunham, Peng Chen, John A. Rogers and Mary B. Chan-Park
RSC Adv., 2012, Advance Article, DOI: 10.1039/C1RA00817J, Communication
