Purification of Semiconducting Carbon Nanotubes

In general, all preparation methods for single-walled carbon nanotubes (CNTs) yield a mixture of semiconducting and metallic CNTs, which differ in their structure and electronic properties, a serious drawback for their practical use in electronic devices. Recently, a technique for obtaining pure semiconducting CNTs (see schematic) was reported – selective etching of the metallic CNTs in methane plasma. This method can be applied to wafer-scale treatment of CNT films and is an important advance for CNT electronics.