Single-walled carbon nanotubes (SWCNTs) are very important material for many applications. The chemical functionalization of carbon nanotubes such as covalent, noncovalent modifications, substitution of carbon atoms in walls, intercalation, filling allow modifying precisely the properties of carbon nanotubes. Here I perform the filling of SWCNTs with gallium selenide [1], lead halogenides [2], and rubidium iodide [3], and investigate the properties with Raman spectroscopy, near edge X-ray absorption fine structure spectroscopy, photoemission spectroscopy, optical absorption spectroscopy [4]. It is shown that the introduced salt leads to the modification of the electronic properties of carbon nanotubes [5]. The p-doping is observed. The successful filling of carbon nanotubes with high filling ratio and high doping level of SWCNTs can find applications in different fields.

[1] M. V. Kharlamova. Novel approach to tailoring the electronic properties of single-walled carbon nanotubes by the encapsulation of high-melting gallium selenide using a single-step process, JETP letters, 2013, V. 98, № 5, p. 272-277

[2] M. V. Kharlamova, C. Kramberger, P. Rudatis, T. Pichler, D. Eder. Revealing the doping effect of encapsulated lead halogenides on single‑walled carbon nanotubes, Appled Physics A, 2019, V. 125, article number 320

[3] M. V. Kharlamova, C. Kramberger, P. Rudatis, K. Yanagi, D. Eder. Characterization of the electronic properties of single-walled carbon nanotubes filled with an electron donor - rubidium iodide: multifrequency Raman and X-ray photoelectron spectroscopy studies, Physica Status Solidi B, 2019, V. 256, № 12, article number 1900209

[4] M. V. Kharlamova, C. Kramberger. Spectroscopy of filled single-walled carbon nanotubes. Nanomaterials 2022, 12, 42.

[5] M. V. Kharlamova. Advances in tailoring the electronic properties of single-walled carbon nanotubes, Progress in Materials Science, 2016, V. 77, p. 125-211