У оквиру семинара Центра за физику чврстог стања и нове материјале Института за физику у Београду, у петак, 10. октобра 2025. године У 12 часова у читаоници библиотеке „Др Драган Поповић“, др Бојана Вишић (Институт за физику у Београду) одржаће предавање:
Van der Waals nanotubes- from synthesis to applications
САЖЕТАК:
Semiconducting transition metal dichalcogenides (TMDCs) can be synthesized in a wide range of structures and geometries, including closed cage nanostructures, such as nanotubes (NTs) or fullerene-like nanoparticles. Individual multiwalled WS2 and MoS2 NTs are having a resurgence of interest, as interesting optical and electrical properties have been reported in recent years [1,2]. They are especially intriguing due to their stability, enhanced light-matter interactions, and ability to sustain exciton-polaritons in ambient conditions, i.e., strong coupling of excitonic resonances to the optical cavity. Namely, these nanotubes act as quasi-1D polaritonic nanosystems and sustain both excitonic features and cavity modes in the visible-near infrared range. This ability to confine light to subwavelength dimensions under ambient conditions is induced by the high refractive index of WS2.
On the other hand, NTs have been vastly neglected as possible alloyed TMDC. Most of the research so far, both theoretically and experimentally, focused on flat, two-dimensional structures, with only a few reports that focused on non-carbon-based alloyed NTs [3]. Additionally, TMDCs have opened a new frontier in the area of field emission devices, due to their layered structure and the presence of thin and sharp edges with high aspect ratios which enhance the local electric field. We grew highly crystalline multiwalled Mo1-xWxS2 NTs via the chemical vapour transport method, with the molybdenum and tungsten atoms randomly distributed within the crystal structure [4]. A detailed analysis of the ED patterns from an eight-layer nanotube revealed that they grow in the 2H structure, with each shell consisting of one bilayer. The work function of the NTs is comparable than that of pure MoS2 and lower of pure WS2 NTs, making them ideal candidates for field emission applications.
Various TMDC NTs promise a wide spectrum of physical effects beyond the physics of CNTs [2]. They have a high aspect ratio, high specific surface area and excellent mechanical and vibrational/acoustic properties, making them suitable as composite nanofillers as only a small amount can be used for forming a conductive path [5]. Furthermore, MS2 NTs disperse well in all commonly used solvents, simplifying composite preparation [6].
B. Višić, et al., Phys. Rev. Res. 1 3 (2019).
B. Višić, et al., JACS 139 12865-78 (2017).
M. B. Sreedhara, et al., J Am Chem Soc 144 232 (2022).
L. Pirker, et al., Adv. Funct. Mater 33 15 (2023).
R. Evarestov, et al., Materials Research Express 5 115028 (2018).
L. Yadgarov, et al., Physical Chemistry Chemical Physics 20 20812-20 (2018).