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arXiv · 1405.7661

Why do nanotubes grow chiral?

Vasilii I. Artyukhov·Evgeni S. Penev·Boris I. Yakobson
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Abstract

Carbon nanotubes (CNT) hold enormous technological promise. It can only be harnessed if one controls in a practical way the CNT chirality, the feature of the tubular carbon topology that governs all the CNT properties---electronic, optical, mechanical. Experiments in catalytic growth over the last decade have repeatedly revealed a puzzling strong preference towards minimally-chiral (near-armchair) CNT, challenging any existing hypotheses and turning chirality control ever more tantalizing yet leaving its understanding elusive. Here we combine the CNT/catalyst interface thermodynamics with the kinetic growth theory to show that the unusual near-armchair peaks emerge from the two antagonistic trends: energetic preference towards achiral CNT/catalyst interfaces vs. faster growth of chiral CNT. This narrow distribution is profoundly related with the peaked behavior of a simple function, x*exp(-x).

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Vasilii I. Artyukhov, Evgeni S. Penev, Boris I. Yakobson. 2014-05-29. Why do nanotubes grow chiral?. https://doi.org/10.1038/ncomms5892

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