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Theoretical prediction of HfB₂ monolayer, a two-dimensional Dirac cone material with remarkable Fermi velocity.

ABSTRACT: Searching for new two-dimensional (2D) Dirac cone materials has been popular since the discovery of graphene with a Dirac cone structure. Based on density functional theory (DFT) calculations, we theoretically designed a HfB₂ monolayer as a new 2D Dirac material by introducing the transition metal Hf into a graphene-like boron framework. This newly predicted HfB₂ monolayer has pronounced thermal and kinetic stabilities along with a Dirac cone with a massless Dirac fermion and Fermi velocities (3.59 × 10⁵ and 6.15 × 10⁵ m s^-1) comparable to that of graphene (8.2 × 10⁵ m s^-1). This study enriches the diversity and promotes the application of 2D Dirac cone materials.

SUBMITTER: Liu Z

PROVIDER: S-EPMC9059940 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Theoretical prediction of HfB2 monolayer, a two-dimensional Dirac cone material with remarkable Fermi velocity.

Liu Zhongfei Z Wang Peihong P Cui Qiaoyu Q Yang Guang G Jin Shaowei S Xiong Kuangwei K

RSC advances 20190121 5

Searching for new two-dimensional (2D) Dirac cone materials has been popular since the discovery of graphene with a Dirac cone structure. Based on density functional theory (DFT) calculations, we theoretically designed a HfB2 monolayer as a new 2D Dirac material by introducing the transition metal Hf into a graphene-like boron framework. This newly predicted HfB2 monolayer has pronounced thermal and kinetic stabilities along with a Dirac cone with a massless Dirac fermion a ...[more]

PMID: 35520500

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