Selective separation and enrichment of semiconducting carbon nanotube using gel and dielectrophoresis and its application for sensor

碳纳米管(CNT)气体传感器因其优异的性能而受到人们的广泛关注。然而，由于具有不同手性的碳纳米管共存，碳纳米管传感器的性能并没有得到优化。本研究展示了一种基于旋转柱层析和介电泳法(DEP)的手性选择性碳纳米管气敏传感器的制备方法。经过三个旋转柱，将原始的碳纳米管分离成三个组分，其中含有不同手性的碳纳米管。利用DEP将碳纳米管固定在微电极上，制成三个碳纳米管气敏传感器。对这些碳纳米管传感器对NO2气体的响应进行了比较，发现传感器的响应依赖于碳纳米管的手性，手性分离可以改善传感器的响应。

Carbon nanotube (CNT) gas sensors have received considerable attention because of their outstanding properties. The CNT sensor performance, however, has not been optimized because of the coexistence of CNTs with different electronic properties depending on their chirality. This study demonstrates a chirality-selective fabrication method of the CNT gas sensor using spin-column chromatography and dielectrophoresis (DEP). After passing through three spin-columns, pristine CNTs were separated into three fractions, which contained CNTs with different chiralities. The CNTs in each fraction were trapped on the microelectrodes by DEP to fabricate three CNT gas sensors. Comparison of these CNT gas sensor responses to NO2 gas revealed that the sensor response was dependent on the CNT chirality and could be improved by the chirality separation.