We performed endohedral functionalization of high-purity metallicity-sorted semiconducting and metallic single-walled carbon nanotubes (SWCNTs) with a mean diameter of 1.4 nm with silver chloride (AgCl) by the method of capillary filling with the melt. The AgCl-filled SWCNTs were investigated by high-resolution scanning transmission electron microscopy and spectroscopic techniques, such as Raman spectroscopy, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy, which were combined to study comprehensively the modified electronic properties of the filled SWCNTs. The data revealed a downshift of the Fermi level of the nanotubes upon filling, i.e., a p-doping of SWCNTs.
