Optical and Conductive Characteristics of Metallic Single-Wall Carbon Nanotubes with Three Basic Colors; Cyan, Magenta, and Yellow

We present protocols to prepare high-purity metallic single-wall carbon nanotubes (SWCNTs) with three basic colors, cyan, magenta, and yellow, through density gradient centrifugations. Addition of deoxycholate sodium salts as a co-surfactant could improve separation capability for metallic SWCNTs in centrifugations. We applied the improved separation protocols to the SWCNTs with different average diameters (1.34, 1.0, and 0.84 nm), and obtained the metallic SWCNTs with cyan, magenta, and yellow colors. Their optical/conductive characteristics were revealed, and conductive color films were formed from the metallic SWCNTs.