Superaligned arrays, films, and yarns of carbon nanotubes: a road toward applications

Abstract

Carbon nanotube (CNT) array is a self-organized highly oriented structure, in which CNTs are vertically aligned on the substrate. Superaligned CNT array is a special kind of vertically aligned CNT array with the unique capability of being converted into pure CNT films or yarns simply by drawing in dry state. The as-converted CNT films are tens of nanometers in thickness, transparent, and highly conductive, with aligned CNTs parallel to the drawing direction. After passing through volatile solutions or being twisted, CNT films can be further condensed into shrunk yarns. These shrunk yarns possess high tensile strengths and Young’s moduli, and are good conductors. The continuous films and yarns have turned nanometer sized CNTs into a manipulable macroscopic object, brought the excellent properties into macroscopic applications, and opened up a road leading from nano-world to macro-world. In this paper, the applications of CNT films and shrunk yarns will be reviewed. Real products made from superaligned CNTs such as TEM grids, loudspeakers, and touch screens will be introduced.