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arXiv · 1612.03237

Carbon-Rich Carbon Nitride Monolayers with Dirac Cones: Dumbbell C4N

Linyang Li·Xiangru Kong·Ortwin Leenaerts·Xin Chen·Biplab Sanyal·François M. Peeters
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Abstract

Two-dimensional (2D) carbon nitride materials play an important role in energy-harvesting, energy-storage and environmental applications. Recently, a new carbon nitride, 2D polyaniline (C3N) was proposed [PNAS 113 (2016) 7414-7419]. Based on the structure model of this C3N monolayer, we propose two new carbon nitride monolayers, named dumbbell (DB) C4N-I and C4N-II. Using first-principles calculations, we systematically study the structure, stability, and band structure of these two materials. In contrast to other carbon nitride monolayers, the orbital hybridization of the C/N atoms in the DB C4N monolayers is sp3. Remarkably, the band structures of the two DB C4N monolayers have a Dirac cone at the K point and their Fermi velocities are comparable to that of graphene. This makes them promising materials for applications in high-speed electronic devices. Using a tight-binding model, we explain the origin of the Dirac cone.

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Linyang Li, Xiangru Kong, Ortwin Leenaerts, Xin Chen, Biplab Sanyal, François M. Peeters. 2016-12-10. Carbon-Rich Carbon Nitride Monolayers with Dirac Cones: Dumbbell C4N. https://arxiv.org/abs/1612.03237

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