The Effects of Lengths of Flavin Surfactant N -10-Alkyl Side Chains on Promoting Dispersion of a High-Purity and Diameter-Selective Single-Walled Nanotube

• Published in: Nanomaterials (Basel, Switzerland) Vol. 12; no. 19; p. 3380
• Main Authors: Park, Minsuk, Hwang, Seongjoo, Ju, Sang-Yong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 27.09.2022; MDPI
• Subjects: Carbon; Chains; Chirality; Chromatography; diameter selectivity; dispersibility; Dispersions; Flavin; Impurities; Nanotechnology; Nanotubes; NMR; Nuclear magnetic resonance; Purity; Selectivity; Self-assembly; side chain length; Single wall carbon nanotubes; single-walled carbon nanotube; Solubility parameters; Sonication; Surfactants; tandem; Canada; United Kingdom > UK; United States > US; Japan; Germany; diameter selectivity; single-walled carbon nanotube; flavin; dispersibility; tandem; side chain length
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano12193380

Flavin with defined helical self-assembly helps to understand chemical designs for obtaining high-purity semiconducting ( )-single-walled carbon nanotubes (SWNT) in a diameter ( )-selective manner for high-end applications. In this study, flavins containing 8, 12, 16, and 20 -alkyl chains were synthesized, and their single/tandem effects on -selective -SWNT dispersibility were investigated at isomolarity. Flavins with -dodecyl and longer chain lengths (FC12, FC16, and FC20) act as good surfactants for stable SWNT dispersions whereas -octyl flavin (FC8) exhibits poor dispersibility owing to the lack of SWNT buoyancy. When used with small- SWNT, FC8 displays chirality-selective SWNT dispersion. This behavior, along with various flavin helical motifs, prompts the development of criteria for 'side chain length ( )' required for stable and -selective SWNT dispersion, which also explains -dependent -enrichment behavior. Moreover, SWNT dispersions with flavins with dodecyl and longer exhibit increased metallic ( )-SWNT, background absorption-contributing carbonaceous impurities (CIs) and preferential selectivity of -SWNT with slightly larger . The increased CIs that affect the SWNT quantum yield were attributed to a solubility parameter. Furthermore, the effects of flavin , sonication bath temperature, centrifugal speed, and surfactant concentration on SWNT purity and -/ -SWNT ratio were investigated. A tandem FC8/FC12 provides fine-tuning of -selective SWNT dispersion, wherein the FC8 ratio governs the tendency towards smaller . Kinetic and thermodynamic assemblies of tandem flavins result in different sorting behaviors in which wide -tunability was demonstrated using kinetic assembly. This study highlights the importance of appropriate side chain length and other extrinsic parameters to obtain -selective or high-purity -SWNT.