Transformation of individual MWCNTs structure after impact ion and electron irradiation

Abstract

Multiwalled carbon nanotubes subjected to irradiation with argon ions, protons and electrons was studied. The transmission electron microscopy and Raman spectroscopy were used to investigate changes in the structure of individual MWCNTs. It is established that irradiation with ions and electrons lead to change in the interlayer distance of the MWCNTs and create volume defects by removing fragments from the outer layers of nanotubes. Analysis of the Raman data shows that irradiation with charged particles leads to a change in the diameters of internal layers of the MWCNTs. Modeling the structure of graphene layers with defects was performed within the framework of the density functional theory. Calculations showed that vacancy defects in the graphene structure lead to a significant decrease in the linear dimensions of the unit cell of graphene. Comparing the theoretical calculations and experimental data, it can be concluded that the change in the interlayer distance of the MWCNT is due to vacancy defects in graphene layers, as well as to the change in the interlayer interaction after introduction of radiation defects.