High-quality, highly concentrated semiconducting single-wall carbon nanotubes for use in field effect transistors and biosensors.

We developed a simple and scalable selective synthesis method of high-quality, highly concentrated semiconducting single-wall carbon nanotubes (s-SWCNTs) by in situ hydrogen etching. Samples containing ~93% s-SWCNTs were obtained in bulk. These s-SWCNTs with good structural integrity showed a high oxidation resistance temperature of ~800 °C. Thin-film transistors based on the s-SWCNTs demonstrated a high carrier mobility of 21.1 cm(2) V(-1) s(-1) at an on/off ratio of 1.1 × 10(4) and a high on/off ratio of 4.0 × 10(5) with a carrier mobility of 7.0 cm(2) V(-1) s(-1). A biosensor fabricated using the s-SWCNTs had a very low dopamine detection limit of 10(-18) mol/L at room temperature.