Spontaneous twisting of a collapsed carbon nanotube

Here we study the collapsing and spontaneous twisting of a carbon nanotube by in situ transmission electron microscopy (TEM). This work was developed in close collaboration with the research group of Prof. Zettl from the University of California, Berkeley.

Hamid Reza Barzegar, Aiming Yan, Sinisa Coh, Eduardo Gracia-Espino, Claudia Ojeda-Aristizabal, Gabriel Dunn, Marvin L. Cohen, Steven G. Louie, Thomas Wågberg, and Alex Zettl. Nano Res. (2017). doi:10.1007/s12274-016-1380-7

Abstract

We study the collapsing and subsequent spontaneous twisting of a carbon nanotube by in situ transmission electron microscopy (TEM). A custom-sized nanotube is first created in the microscope by selectively extracting shells from a parent multi-walled tube. The few-walled, large-diameter daughter nanotube is driven to collapse via mechanical stimulation, after which the ribbon-like collapsed tube spontaneously twists along its long axis. In situ diffraction experiments fully characterize the uncollapsed and collapsed tubes. The experimental observations and associated theoretical analysis indicate that the origin of the twisting is compressive strain.