On-chip diameter-dependent conversion of metallic to semiconducting single-walled carbon nanotubes by immersion in 2-ethylanthraquinone

• Main Authors: Rogers, John A., Chan-Park, Mary B., Li, Jiangbo, Luan, Xuena, Huang, Yinxi, Dunham, Simon, Chen, Peng
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2013
• Online Access: https://hdl.handle.net/10356/97028; http://hdl.handle.net/10220/10412
• Institution: Nanyang Technological University

The key hurdle to the practical use of as-grown single-walled carbon nanotubes (SWNTs) for high performance nanoelectronics is the unavoidable presence of metallic nanotubes with current synthesis methods. We present a simple approach to convert metallic SWNTs to semiconducting ones in situ to improve device field effect behaviour, using an aromatic compound (2-ethylanthraquinone - EAQ) which is a mild radical initiator. We show that the reaction between EAQ-generated radicals and SWNTs is diameter and metallicity dependent; in the medium-diameter regime (0.8 to 1.0 nm), the EAQ-generated radicals preferentially attack the metallic SWNTs over semiconducting ones and convert them to semiconducting, as evidenced by several orders (10 and 104) increase in the on/off ratio.