超高純度かつ高結晶性半導体カーボンナノチューブの迅速分離法の開発と伝導特性評価

单壁碳纳米管（SWCNTs）是一种很有前途的高性能半导体器件材料，如薄膜晶体管（tft）。然而，SWCNTs通常同时具有金属和半导体性质，这取决于其结构。此外，半导体SWCNTs （s-SWCNTs）还具有不同的载流子迁移率，其迁移率与其直径成反比。因此，纯化大直径s-SWCNTs是实现其高性能tft应用的必要条件。在这里，我们展示了使用温控凝胶过滤和低组成梯度洗脱相结合的方法纯化大直径s-SWCNTs。通过将分离温度控制在310K，大直径s-SWCNTs被充分吸附在柱上，而大直径金属SWCNTs （m-SWCNTs）通过柱。随后，低组成梯度洗脱将大直径s-SWCNTs与小直径s-SWCNTs和m-SWCNTs分离。因此，成功分离了平均直径为1.9 nm的s-SWCNTs，并将其用于制备tft。与通常获得的1.5 nm直径s-SWCNTs制备的TFT相比，1.9 nm直径s-SWCNTs制备的TFT载流子迁移率高1.6倍，电流密度高1.3倍。因此，我们不仅成功纯化了大直径s-SWCNTs，而且证明了它们比通常纯化的小直径s-SWCNTs具有更优越的性能。

Single-wall carbon nanotubes (SWCNTs) are promising materials for high performance semiconductor devices application such as thin-film transistors (TFTs). However, SWCNTs are typically exhibit both metallic and semiconducting properties depend on the structure. In addition, the semiconducting SWCNTs (s-SWCNTs) also has various carrier mobility which inversely related to their diameter. Thus, purifying large diameter s-SWCNTs is necessary to realize their high performance TFTs application. Here, we demonstrate the purification of large diameter s-SWCNTs using combination of temperature-controlled gel filtration and low composition gradient elution. By controlling the separation temperature at 310K, large diameter s-SWCNTs are sufficiently adsorbed on the column while the large diameter metallic SWCNTs (m-SWCNTs) pass through the column. Subsequently, low composition gradient elution separate the large diameter s-SWCNTs from the small diameter s-SWCNTs and m-SWCNTs. Thus, s-SWCNTs with average diameter of 1.9 nm has been successfully separated and used to fabricate TFTs. Compared to those fabricated from the typically obtained 1.5-nm-diameter s-SWCNTs, the TFT fabricated from 1.9-nm-diameter s-SWCNTs exhibit 1.6 times higher carrier mobility and 1.3 times higher on current density. Therefore, we have not only succeeded in purifying large diameter s-SWCNTs, but also demonstrate their superior performance than the small diameter s-SWCNTs which are typically purified.