Enrichment of semiconducting-SWNTs using thiophene based conjugated polymers with high alkyl side-chain density for thin film transistors

Abstract

In the development of post-sorting methods for single-walled carbon nanotubes (SWNTs) with identical electrical property, conjugated polymers (CP) have received significant attention due to their high yield and purity sorting ability. The high purity of semiconducting SWNTs isolated from as-synthesized SWNTs can be one of potential materials in low-cost large-area printed electronics including thin film transistors (TFTs). Many studies demonstrated the ability of a various types of CP such as polyfluorene, but thiophenebased polymers have not been widely investigated to selectively separate a particular chirality of SWNT. Herein, we selectively sort SWNTs using thiophene based CPs with different alkyl chain density via simple centrifugation steps. A high density of polymer shows good sorting ability showing high purity of above 99%. Finally, the fabricated SWNTs based bottom gate-bottom contact TFTs display p-dominant property and the obtained best mobility is 8.69 cm2 V−1 S−1 .