In-situ TEM and EELS studies of alkali–metal intercalation with single-walled carbon nanotubes

Cesium (Cs) or potassium (K) was deposited on single-walled carbon nanotube bundles in vacuum at room temperature. The deposited bundles were analyzed in-situ by transmission electron microscopy and electron energy loss spectroscopy techniques. The results indicate that both Cs and K can be reversibly intercalated with the bundles. The intercalants reside in-between the individual nanotubes within the bundles. Intercalation caused structural disorder to the two-dimensional lattice of the pristine nanotube bundles. The chemical compositions of the nanotube bundles intercalated with K and Cs were found to be about KC24 and CsC24 to CsC8.