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Stabilities and novel electronic structures of three carbon nitride bilayers
We predict three novel phases of the carbon nitride (CN) bilayer, denoted α-C(2)N(2), β-C(2)N(2) and γ-C(4)N(4), respectively. All of them consist of two CN sheets connected by C-C covalent bonds. The phonon dispersions reveal that all these phases are dynamically stable, because no imaginary freque...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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Nature Publishing Group UK
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6355783/ https://www.ncbi.nlm.nih.gov/pubmed/30705289 http://dx.doi.org/10.1038/s41598-018-37100-w |
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author | Lin, Wanxing Liang, Shi-Dong He, Chunshan Xie, Wucheng He, Haiying Mai, Quanxiang Li, Jiesen Yao, Dao-Xin |
author_facet | Lin, Wanxing Liang, Shi-Dong He, Chunshan Xie, Wucheng He, Haiying Mai, Quanxiang Li, Jiesen Yao, Dao-Xin |
author_sort | Lin, Wanxing |
collection | PubMed |
description | We predict three novel phases of the carbon nitride (CN) bilayer, denoted α-C(2)N(2), β-C(2)N(2) and γ-C(4)N(4), respectively. All of them consist of two CN sheets connected by C-C covalent bonds. The phonon dispersions reveal that all these phases are dynamically stable, because no imaginary frequency is present. The transition pathway between α-C(2)N(2) and β-C(2)N(2) is investigated, which involves bond-breaking and bond-reforming between C and N. This conversion is difficult, since the activation energy barrier is 1.90 eV per unit cell, high enough to prevent the transformation at room temperature. Electronic structure calculations show that all three phases are semiconductors with indirect band gaps of 3.76/5.22 eV, 4.23/5.75 eV and 2.06/3.53 eV, respectively, by PBE/HSE calculation. The β-C(2)N(2) has the widest band gap among the three phases. All three bilayers can become metallic under tensile strain, and the indirect gap of γ-C(4)N(4) can turn into a direct one. γ-C(4)N(4) can become an anisotropic Dirac semimetal under uniaxial tensile strain. Anisotropic Dirac cones with high Fermi velocity of the order of 10(5) m/s appear under 12% strain. Our results suggest that the three two-dimensional materials have potential applications in electronics, semiconductors, optics and spintronics. |
format | Online Article Text |
id | pubmed-6355783 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-63557832019-02-01 Stabilities and novel electronic structures of three carbon nitride bilayers Lin, Wanxing Liang, Shi-Dong He, Chunshan Xie, Wucheng He, Haiying Mai, Quanxiang Li, Jiesen Yao, Dao-Xin Sci Rep Article We predict three novel phases of the carbon nitride (CN) bilayer, denoted α-C(2)N(2), β-C(2)N(2) and γ-C(4)N(4), respectively. All of them consist of two CN sheets connected by C-C covalent bonds. The phonon dispersions reveal that all these phases are dynamically stable, because no imaginary frequency is present. The transition pathway between α-C(2)N(2) and β-C(2)N(2) is investigated, which involves bond-breaking and bond-reforming between C and N. This conversion is difficult, since the activation energy barrier is 1.90 eV per unit cell, high enough to prevent the transformation at room temperature. Electronic structure calculations show that all three phases are semiconductors with indirect band gaps of 3.76/5.22 eV, 4.23/5.75 eV and 2.06/3.53 eV, respectively, by PBE/HSE calculation. The β-C(2)N(2) has the widest band gap among the three phases. All three bilayers can become metallic under tensile strain, and the indirect gap of γ-C(4)N(4) can turn into a direct one. γ-C(4)N(4) can become an anisotropic Dirac semimetal under uniaxial tensile strain. Anisotropic Dirac cones with high Fermi velocity of the order of 10(5) m/s appear under 12% strain. Our results suggest that the three two-dimensional materials have potential applications in electronics, semiconductors, optics and spintronics. Nature Publishing Group UK 2019-01-31 /pmc/articles/PMC6355783/ /pubmed/30705289 http://dx.doi.org/10.1038/s41598-018-37100-w Text en © The Author(s) 2019 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Lin, Wanxing Liang, Shi-Dong He, Chunshan Xie, Wucheng He, Haiying Mai, Quanxiang Li, Jiesen Yao, Dao-Xin Stabilities and novel electronic structures of three carbon nitride bilayers |
title | Stabilities and novel electronic structures of three carbon nitride bilayers |
title_full | Stabilities and novel electronic structures of three carbon nitride bilayers |
title_fullStr | Stabilities and novel electronic structures of three carbon nitride bilayers |
title_full_unstemmed | Stabilities and novel electronic structures of three carbon nitride bilayers |
title_short | Stabilities and novel electronic structures of three carbon nitride bilayers |
title_sort | stabilities and novel electronic structures of three carbon nitride bilayers |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6355783/ https://www.ncbi.nlm.nih.gov/pubmed/30705289 http://dx.doi.org/10.1038/s41598-018-37100-w |
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