Separation of Ultrahigh‐Purity Long Semiconducting Carbon Nanotubes via Gel Chromatography

Abstract Mass production of ultrahigh‐purity long semiconducting single‐wall carbon nanotubes (s‐SWCNTs) is essential for their utilization in high‐performance carbon‐based devices. Here, the separation of ultrahigh‐purity long s‐SWCNTs is achieved by integrating repeated short‐duration ultrasonic dispersion with iterative separation via gel chromatography. The resulting s‐SWCNTs are confirmed to have a purity exceeding 99.9999%, representing the highest purity achieved via surfactant‐based separation methods. Additionally, the average length of the separated s‐SWCNTs exceeds 430 nm, with ≈47% surpassing 400 nm in length—more than twice the length of those obtained through traditional dispersion and separation methods. From these, a subset of s‐SWCNTs with an average length of ≈674 nm and 79.8% exceeding 400 nm is further extracted for fabricating SWCNT thin‐film transistors. The resulting transistors exhibit markedly superior transport performance compared to those derived from s‐SWCNTs produced via conventional methods, characterized by significantly higher on‐state conductance of ≈149 µS µm −1 , higher carrier mobility of over 89.1 cm 2 V −1 s −1 and a high on/off ratio exceeding 10⁵. The work demonstrates the exceptional separation capability of surfactant‐based gel chromatography in producing ultrahigh‐purity long s‐SWCNTs with minimal defects, which holds significant promise for advancing the application of SWCNTs in high‐performance electronic devices.