Simulating Raman spectra by combining first-principles and empirical potential approaches with application to defective MoS2
Loading...
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Date
Department
Major/Subject
Mcode
Degree programme
Language
en
Pages
7
Series
npj Computational Materials, Volume 6, issue 1, pp. 1-7
Abstract
Successful application of two-dimensional transition metal dichalcogenides in optoelectronic, catalytic, or sensing devices heavily relies on the materials’ quality, that is, the thickness uniformity, presence of grain boundaries, and the types and concentrations of point defects. Raman spectroscopy is a powerful and nondestructive tool to probe these factors but the interpretation of the spectra, especially the separation of different contributions, is not straightforward. Comparison to simulated spectra is beneficial, but for defective systems first-principles simulations are often computationally too expensive due to the large sizes of the systems involved. Here, we present a combined first-principles and empirical potential method for simulating Raman spectra of defective materials and apply it to monolayer MoS2 with random distributions of Mo and S vacancies. We study to what extent the types of vacancies can be distinguished and provide insight into the origin of different evolutions of Raman spectra upon increasing defect concentration. We apply to our simulated spectra the phonon confinement model used in previous experiments to assess defect concentrations, and show that the simplest form of the model is insufficient to fully capture peak shapes, but a good match is obtained when the type of phonon confinement and the full phonon dispersion relation are accounted for.Description
Keywords
Other note
Citation
Kou, Z, Hashemi, A, Puska, M J, Krasheninnikov, A V & Komsa, H P 2020, 'Simulating Raman spectra by combining first-principles and empirical potential approaches with application to defective MoS 2', npj Computational Materials, vol. 6, no. 1, 59, pp. 1-7. https://doi.org/10.1038/s41524-020-0320-y