Electrochemical Insertion of Sodium Ion into Nanocarbon Materials for Sodium Ion Batteries

Abstract

The structural changes of single-walled carbon nanotubes (SWCNTs) by the reactions with sodium in a sealed glass tube at high temperature were investigated by Raman scattering and XRD measurements. It was found that sodium atoms are inserted into the nanotube hollow core space in the case of open-end SWCNTs. However, it was shown by electrochemical charge–discharge measurements that the inner space of the nanotubes cannot work as sodium ion adsorption sites when sodium doping was done electrochemically.