Statistical Verification of Anomaly in Chiral Angle Distribution of Air-Suspended Carbon Nanotubes

Abstract

Single-walled carbon nanotubes (SWCNT) have long attracted attention due to their distinct physical properties, depending on their chiral structures (chiralities). Clarifying their growth mechanism is important toward perfect chirality-controlled bulk synthesis. Although a correlation between the chirality distribution and the carbon atom configuration at an open tube edge has been predicted theoretically, lack of sufficient statistical data on metallic and semiconducting SWCNTs prohibited its verification. Here, we report statistical verification of the chirality distribution of 413 as-grown individual air-suspended SWCNTs with a length of over 20 μm using broadband Rayleigh spectroscopy. After excluding the impact of the difference in the number of possible SWCNT structures per chiral angle interval, the abundance profile with chiral angle exhibits an increasing trend with a distinct anomaly at a chiral angle of approximately 20°. These results are well explained considering the growth rate depending on armchair-shaped site configurations at the catalyst–nanotube interface.

Structural Diversity of Single‐Walled Transition Metal Dichalcogenide Nanotubes Grown via Template Reaction

“…We compared this experimental data with the theoretically expected distribution, assuming equal growth probabilities for each ( n,m ) species. In reference to the statistical analysis of CNTs, [ 57 ] the expected value under the random growth condition is given as $$$$\begin{equation} \langle {N}_{\mathrm{R}}\left(\alpha \right)\rangle =\left(\sum N\left(\alpha \right)\right)\ensuremath{\times{}}{P}_{\mathrm{R}}\left(\alpha \right) \end{equation}$$$$where ∑ N ( α ) is the total number of MoS 2 NTs found in the experiments and P R ( α ) is the theoretical probability of finding MoS 2 NTs with a chiral angle α (Figure S5, Supporting Information). P R ( α ) is calculated as P R ( α ) = N R ( α )/(∑ N R ( α )), where N R N R ( α ) is the possible number of chiral indices ( n,m ) with a chiral angle α in diameters ranging from 3 to 10 nm and ∑ N R ( α ) is the total number of ( n,m ) for all θ (0° ≤ α ≤ 30°) within the corresponding diameter range (see Supporting Information for details).…”

“…We compared this experimental data with the theoretically expected distribution, assuming equal growth probabilities for each (n,m) species. In reference to the statistical analysis of CNTs, [57] the expected value under the random growth condition is given as…”

Aerosol Doping System for Microscale Seamless p–n Patterning of Carbon Nanotube Films

“…Various types of TEGs have been developed, such as metal alloys with high thermoelectric conversion capabilities and flexible soft materials suitable for clothing applications. − Recently, single-walled carbon nanotubes (CNTs) have gained increasing attention as a potential thermoelectric material. − Theoretical and experimental studies have proven that controlling specific parameters, such as chirality, length, and carrier concentration, can lead to high thermoelectric conversion ability, as demonstrated by the power factor PF and figure of merit ZT . Various studies on the synthesis, purification, doping, processing, and applications of CNTs have been conducted. − …”

Unveiling the Transformative Potential of SWCNT/In2O3 Heterostructures as High-Performance Catalysts for Overall Water Splitting

“…Single-walled carbon nanotubes (SWCNTs) have captivated enormous consideration and research owing to their unique amalgamation of distinctive features such as high electrical, optical, and mechanical properties; excellent mobility of 10 5 cm 2 V –1 s –1 ; excellent strength-to-weight ratio; diameter-dependent band gap; reinforcement ability; broad spectral absorption; and good thermal and chemical stability. − SWCNTs manifest in various forms, such as metallic, semimetallic, and semiconducting forms, which strongly depend on their diameter and chirality . SWCNTs have variable diameters, harmonizing surface adsorption and desorption chemistry, which could modulate the electrocatalytic properties of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) .…”