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First-Principles Calculation of Optoelectronic Properties in 2D Materials: The Polytypic WS₂ Case.

ABSTRACT: The phenomenon of polytypism, namely unconventional crystal phases displaying a mixture of stacking sequences, represents a powerful handle to design and engineer novel physical properties in two-dimensional (2D) materials. In this work, we characterize from first-principles the optoelectronic properties associated with the 2H/3R polytypism occurring in WS₂ nanomaterials by means of density functional theory (DFT) calculations. We evaluate the band gap, optical response, and energy-loss function associated with 2H/3R WS₂ nanomaterials and compare our predictions with experimental measurements of electron energy-loss spectroscopy (EELS) carried out in nanostructures exhibiting the same polytypism. Our results provide further input to the ongoing efforts toward the integration of polytypic 2D materials into functional devices.

SUBMITTER: Maduro L

PROVIDER: S-EPMC9136949 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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First-Principles Calculation of Optoelectronic Properties in 2D Materials: The Polytypic WS2 Case.

Maduro Louis L van Heijst Sabrya E SE Conesa-Boj Sonia S

ACS physical chemistry Au 20220110 3

The phenomenon of polytypism, namely unconventional crystal phases displaying a mixture of stacking sequences, represents a powerful handle to design and engineer novel physical properties in two-dimensional (2D) materials. In this work, we characterize from first-principles the optoelectronic properties associated with the 2H/3R polytypism occurring in WS2 nanomaterials by means of density functional theory (DFT) calculations. We evaluate the band gap, optical response, and energy-lo ...[more]

PMID: 35637785

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