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Influence of Alkyne Precursor Structure on Carbon Nanotube Chiral Distribution: Data-Dense Analysis Across Multiple
Eric P Johnson1,2, Sei Jin Park3, Eric R Meshot3
1Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States.
ACS Nano
|November 19, 2025
Summary
Researchers explored how precursor structure affects carbon nanotube (CNT) chirality. While not dictating specific chirality, precursor structure influences chiral distribution, with catalyst structure playing a key role in CNT growth.
Area of Science:
- Materials Science
- Nanotechnology
- Chemical Engineering
Background:
- Carbon nanotubes (CNTs) possess tunable electronic properties dependent on chirality (diameter and lattice angle), making them valuable for optoelectronics and semiconductors.
- Current industrial synthesis yields chiral mixtures, necessitating costly post-synthesis separation, hindering large-scale applications.
- Controlling CNT chirality during synthesis is crucial for efficient manufacturing.
Purpose of the Study:
- To investigate the impact of terminal alkyne precursor structure on the chiral distribution of synthesized carbon nanotubes.
- To evaluate the influence of various transition-metal catalysts on CNT chirality.
- To understand the relationship between precursor structure, catalyst, and CNT growth mechanism.
Main Methods:
- Synthesis of CNTs using seven distinct terminal alkyne precursors and five transition-metal catalysts (Fe, FeMo, CoMo variants).
- Characterization of CNT chirality and diameter distribution via multiwavelength Raman spectroscopy across 5,145 measurement spots.
- Analysis of precursor structure effects on chiral distribution and correlation with catalyst type.
Main Results:
- Acetylene precursor resulted in the smallest diameter CNTs.
- Vinylacetylene precursor led to fewer subnanometer CNTs compared to other precursors.
- Precursor structure modulated the breadth of chiral distribution, but catalyst structure was the dominant factor influencing chirality.
Conclusions:
- Precursor structure influences CNT chiral distribution, affecting the range of diameters and chiral angles produced.
- Catalyst composition plays a more significant role than precursor structure in determining CNT chirality.
- The findings support a growth mechanism involving metal-precursor binding through unsaturated bonds via alkyne polymerization.
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