Digital Isotope Coding to Trace the Growth Process of Individual Single-Walled Carbon Nanotubes

Abstract

Single-walled carbon nanotubes (SWCNTs) are attracting increasing attention as an ideal material for high-performance electronics through the preparation of arrays of purely semiconducting SWCNTs. Despite significant progress in the controlled synthesis of SWCNTs, their growth mechanism remains unclear due to difficulties in analyzing the time-resolved growth of individual SWCNTs under practical growth conditions. Here we present a method for tracing the diverse growth profiles of individual SWCNTs by embedding digitally coded isotope labels. Raman mapping showed that, after various incubation times, SWCNTs elongated monotonically until their abrupt termination. Ex situ analysis offered an opportunity to capture rare chirality changes along the SWCNTs, which resulted in sudden acceleration/deceleration of the growth rate. Dependence on growth parameters, such as temperature and carbon concentration, was also traced along individual SWCNTs, which could provide clues to chirality control. Systematic growth studies with a variety of catalysts and conditions, which combine the presented method with other characterization techniques, will lead to further understanding and control of chirality, length, and density of SWCNTs.

Deterministic transfer of optical-quality carbon nanotubes for atomically defined technology

“…2 e). The measured heights of the CNTs fall within the typical diameter range of those on the growth substrates 29 . It is noteworthy that the anthracene stamp gives rise to only one tenth as much contamination as a PDMS stamp (Fig.…”

“…The improved transfer yield of the anthracene-assisted method may partially originate from the fact that 100% of the picked-up CNTs are released on the receiving substrates together with the anthracene crystals. We should note that the pick-up efficiency by the anthracene crystals is much higher for small diameter CNTs (~1 nm), but the diameter range of CNTs on quartz under the current growth condition (1.42 ± 0.17 nm 29 ) lies outside of the optimal range (Supplementary Fig. 3 ).…”

“…We use three types of CNT synthesis in this study. The arrays of long CNTs are grown on single-crystalline quartz substrates 29 . Iron catalyst nanoparticles with a nominal thickness of 0.2 nm are deposited on lithographically patterned stripes.…”

Precise Synthesis of Carbon Nanotubes and One‐Dimensional Hybrids from Templates†

“…[ 24,26,130 ] It was reported that any defects such as the pentagon‐heptagon pair in a SWCNT will change the local chirality. [ 131‐133 ] When disturbing the growth parameters during CVD, such as changing carbon feeding stocks [ 88,134 ] and introducing an electric field, [ 135 ] the as‐grown SWCNTs exhibited heterojunctions with different chiralities. With this strategy, the SWCNTs with high‐ purity electronic type [ 135 ] and specific chirality were obtained.…”

Universal map of gas-dependent kinetic selectivity in carbon nanotube growth

“…1a). Several studies have captured the one-by-one growth rates by optical or electron microscopy [21][22][23][24], but the results often disagree with each other. Even for the case of alcohols as carbon sources [25], the discrepancy is evident.…”