Engineering and optical characterization of large area, aligned single-wall carbon nanotubes*

Single-wall carbon nanotubes (SWCNTs) possess unique optical and electronic properties due to their strictly one-dimensional nature, that can be enhanced at the macroscopic scale when the SWCNTs are well-aligned. Engineering of a large-scale (mm²) architecture of aligned SWCNTs has challenged the community for years and presents a major drawback in their use in many applications. The reproduction of the first demonstration of high-quality aligned films of SWCNTs was reported by X. He et al. remains a challenge due to insufficient methodical details and a lack of understanding of the role of certain experimental parameters. The goal of our work is to refine their reported method and establish the robust capability to produce aligned macroscopic films at NIST using tubes of varying chiralities and surfactants. Creating monodomain, aligned films utilizing a slow vacuum filtration technique and a rigid protocol varying several parameters, including SWCNT concentration, surfactant concentration, and filtration flow rate. Once films are produced, they need to be transferred from the polycarbonate nanopore membrane used during filtration onto other substrates for device fabrication and characterization, including polarized optical microscopy, Raman spectroscopy, and absorption.