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Indirect-To-Direct Band Gap Transition of One-Dimensional V2Se9: Theoretical Study with Dispersion Energy Correction.

ABSTRACT: Recently, we synthesized a one-dimensional (1D) structure of V2Se9. The 1D V2Se9 resembles another 1D material, Nb2Se9, which is expected to have a direct band gap. To determine the potential applications of this material, we calculated the band structures of 1D and bulk V2Se9 using density functional theory by varying the number of chains and comparing their band structures and electronic properties with those of Nb2Se9. The results showed that a small number of V2Se9 chains have a direct band gap, whereas bulk V2Se9 possesses an indirect band gap, like Nb2Se9. We expect that V2Se9 nanowires with diameters less than ?20 Å would have direct band gaps. This indirect-to-direct band gap transition could lead to potential optoelectronic applications for this 1D material because materials with direct band gaps can absorb photons without being disturbed by phonons.

SUBMITTER: Lee WG

PROVIDER: S-EPMC6844153 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Indirect-To-Direct Band Gap Transition of One-Dimensional V2Se9: Theoretical Study with Dispersion Energy Correction.

Lee Weon-Gyu WG Chae Sudong S Chung You Kyoung YK Yoon Won-Sub WS Choi Jae-Young JY Huh Joonsuk J

ACS omega 20191025 19

Recently, we synthesized a one-dimensional (1D) structure of V2Se9. The 1D V2Se9 resembles another 1D material, Nb2Se9, which is expected to have a direct band gap. To determine the potential applications of this material, we calculated the band structures of 1D and bulk V2Se9 using density functional theory by varying the number of chains and comparing their band structures and electronic properties with tho ...[more]

PMID: 31720541

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