Macroscopically aligned carbon nanotubes for flexible and high-temperature electronics, optoelectronics, and thermoelectrics

Abstract

Abstract The remarkable flexibility, stable chemical structure, and extraordinary thermal, electrical, and optical properties of carbon nanotubes (CNTs) are promising for a variety of applications in flexible and/or high-temperature electronics, optoelectronics, and thermoelectrics, including wearables, refractory photonics, and waste heat harvesting. However, the long-standing problem in the preparation of CNT ensembles is to maintain the extraordinary properties of individual CNTs on a macroscopic scale; the polydispersity and randomness remain two main challenges. In this topical review, we will discuss three ways of creating wafer-scale aligned CNTs: direct growth of aligned CNTs by chemical vapor deposition, production of ultrahigh-conductivity CNT fibers through solution spinning and coating, and spontaneous formation of wafer-scale aligned CNT films via controlled vacuum filtration. We will then describe flexible and high-temperature applications of these materials, such as flexible CNT broadband detectors, flexible strain sensors, spectrally selective thermal emitters, and thermoelectric devices.