Carbon Nanotube Liquid Crystal Dispersion for Large-Area, Micropatterned Aligned Films

Aligned single-walled carbon nanotube (SWCNT) films are potential materials for devices with excellent electrical and optical properties. However, the fabrication of well-aligned SWCNT films is limited, along with practical issues such as the area size and mass production. In this study, we successfully developed a method to fabricate SWCNT films with high alignment by applying an SWCNT dispersion to a substrate using a general wet-coating technique. The prepared SWCNT film showed a high degree of orientation with a nematic order parameter of 0.86 and 0.56 based on Raman spectroscopy and near-infrared (NIR) absorption spectroscopy, respectively. An orientation film several tens of centimeters in length can be prepared on polyethylene terephthalate (PET) film by wet-coating and drying. Furthermore, using the photoresponsive property of the dispersant, micrometer-scale patterning is also possible. The proposed method paves the way for the development of SWCNT-aligned devices for electronic and optical applications, such as the NIR/infrared polarizer and the detector and the electrode.