Comparison of Some Physical Properties of Doped and Pristine Nanotubes Based on Carbon and Tungsten Disulfide

In this work, we present the experimental results on various spectroscopy measurements (including Raman, IR, optical, and terahertz spectroscopies) as well as the data on transmission and scanning electron microscopy of pristine and doped (with HAuCl4) nanotubes (NT) based on carbon (C) and tungsten disulfide (WS2). We observed the peaks of excitonic transitions (semiconducting ES11, ES22, and metallic EM11 transitions with wavelengths 2300, 1240, and 870 nm for CNT and A, B, C, D transitions with wavelengths 670, 550, 500, and 410 nm for WS2NT), Raman active modes (G-band 1585 cm-1 for CNT and E12g 417 cm-1, A1g 351 cm-1 for WS2NT). The behavior of conductivity of the pristine NT in the terahertz range was investigated. With the help of these measurements, the comparison of different pristine NT and their doped analogs was implemented and the shift of the Raman peaks and the changed conductivity behavior for doped nanotubes were found.