-
在二维材料中, 平面六方氮化铝(AlN)对开发电子器件至关重要. 但宽带隙限制了其应用, 为进一步突破性能瓶颈, 本文采用结构搜索的方法找到一种新型孔状皱面的AlN构型, 由于其特殊的孔状构型, 可在孔中引入C、Si原子与碳三角环(TC)形成新型二维X-AlN (X=C, Si与TC)结构,从而提升其光学与热学性能. 结果表明: (1)在电子结构方面, 由于X- pz电子的局域性, 费米面附近产生的孤立能带将带隙值从4.12 eV (AlN)分别降至0.65 (C-AlN)和1.85 eV (Si-AlN), 显著改善了AlN的宽带隙. TC-AlN由于碳三角环间C- pz杂化形成离域π键,使能量降低, 实现了间接-直接带隙的转变. (2)热输运方面, 与AlN、C/Si-AlN相比, TC-AlN由于碳三角环间强共价键抑制了垂直面内的声子振动, 极大的增强了热导率. 此外, 在X-AlN中施加双轴应变, 热导率出现先上升后下降的异常变化趋势, 这是源于随应变增强的N-N键带来的低非谐性与声子模软化降低群速度之间的竞争.本工作给出了调控二维AlN性能的新路径, 为提高半导体电子、光学与热学性能提供有力指导.Aluminum nitride (AlN) are of paramount importance for developing electronic devices because of excellent stability and thermal transport performance. However, lack of novel materials which can provide colorful physical and chemical properties seriously hinder to further digging out application potential. In this work, we perform an evolutionary structural search based on first-principles calculation and verify the dynamic and thermal dynamic stability of porous buckled AlN and X-AlN (X=C, Si, and TC) structural system, which constructs by introducing C, Si atoms and triangular carbon (TC) in the porous vacancy of AlN, by calculating phonon spectra and first-principles molecular dynamic simulations. Structural deformation becomes gradually serious with the increase of structural unit size and significantly influences structural, electronic, and thermal transport properties. In the first, we point out that a flat energy band appears around the Fermi level in C-AlN and Si-AlN because of weak interatomic interaction between C/Si and the neighbor Al atoms. Unoccupied C-/Si- pz and Al- pz do not form π bond and only arises a localized flat band near Fermi level, and thus the absorption peaks of structures are enhanced and occur redshift. Bonding state of π bond from hybridized C- pz orbitals in triangular carbon of TC-AlN lowers the energy of conduction band at K point in the first Brillouin zone and the corresponding antibonding state raises the band at Γ, thus transition from indirect bandgap of AlN to direct bandgap of TC-AlN appears. Secondly, porous buckled AlN shows the lowest thermal conductivity due to asymmetric Al-N bonds around the porous vacancy and vertical stacked N-N bonds. Introduced C and Si atoms both decrease structural anharmonicity, while the former has a relatively small distortion and thus a higher thermal conductivity. Triangular carbon in TC-AlN hinders phonon scattering between FA and other phonon modes and has the weakest anharmonicity because of the strongest bond strength, and obtains the highest thermal transport performance. Finally, we unveil that physical mechanism that anomalous thermal conductivity in X-AlN system by modulation of biaxial tensile strain. Enhanced vertical N-N bonds dominate thermal transport due to its weaker anharmonicity with a slightly strain, and when over the 4% tensile strain, soften phonon modes decrease phonon velocity and thus hinders the thermal transport process. Therefore, the anomalous thermal transport behavior, i.e., thermal conductivity rises first and then drops versus applied biaxial strain, occurs. Our work paves the way to modulate two-dimensional AlN performance and provides new insight for designing promising novel two-dimensional semiconductors.
-
Keywords:
- two-dimensional semiconductor /
- thermal transport /
- electronic structure /
- biaxial stress-strain
-
[1] Robinson J A 2018 APL Mater. 6 058202
[2] Shi L, Xu A, Zhao T 2017 ACS Appl. Mater. Interfaces 9 1987
[3] Cai Y, Liu Y, Xie Y, Zou Y, Gao C, Zhao Y, Liu S, Xu H, Shi J, Guo S, Sun C 2020 APL Mater. 8 021107
[4] Ye Q, Shen Y, Yuan Y, Zhao Y F, Duan C G 2020 Acta Phys. Sin. 69 217710(in Chinese)[叶倩, 沈阳, 袁野, 赵祎峰, 段纯刚2020物理学报69 217710]
[5] Chen R, Wang Y F, Wang Y X, Liang Q, Xie Q 2022 Acta Phys. Sin. 71 127301(in Chinese)[陈蓉, 王远帆, 王熠欣, 梁前, 谢泉2022物理学报 71 127301]
[6] Liang H P, Duan Y F 2022 Chin. Phys. B 31 076301
[7] Lv F, Liang H P, Duan Y F 2023 J. Phys. Chem. Lett. 14 663
[8] Wan X G, Turner A M, Vishwanath A, Savrasov S Y 2011 Phys. Rev. B 83 205101
[9] Liang H P, Duan Y F 2021 Nanoscale 13 11994
[10] Akal L, Kusuki Y, N Shiba, Takayanagi T, Wei Z X 2021 Phys. Rev. Lett. 126 061604
[11] Novoselov K S, Geim A K, Morozov S V, Jiang D, Zhang Y, Dubonos S V, Grigorieva I V, Firsov A 2004 Science 306 666
[12] Lu X B, Zhang G Y 2015 Acta Phys. Sin. 64 077305(in Chinese)[卢晓波, 张广宇2015物理学报64 077305]
[13] Cao Y, Fatemi V, Fang S, Watanabe K, Taniguchi T, Kaxiras E, Jarillo-Herrero P 2018 Nature 556 43
[14] Tan X, Xin Z Y, Liu X J, Mu Q G 2013 Adv. Mater. Research 821-822 841
[15] Shimada K, Sota T, Suzuki K 1998 J. Appl. Phys. 84 4951
[16] Zhang H, Yu S, Liu F, Wang Z, Lu M, Hu X, Chen Y, Xu X 2017 Sci. China-Phys. Mech. Astron. 60 044311
[17] Feng J H, Tang L D, Liu B W, Xia Y, Wang B 2013 Acta Phys. Sin. 62 116302(in Chinese)[冯嘉恒, 唐立丹, 刘邦武, 夏洋, 王冰2013物理学报62 116302]
[18] Lin Z, Guo Z Y, Bi Y Z, Dong Y C 2009 Acta phys. Sin. 58 191707(in Chinese)[林竹, 郭志友, 毕艳君, 董玉成2009物理学报58 191707]
[19] Cheng L, Wang D X, Zhang Y, Su L P, Chen S Y, Wang X F, Sun P, Yi C G 2018 Acta Phys. Sin. 67 047101(in Chinese)[程丽, 王德兴, 张杨, 苏丽萍, 陈淑妍, 王晓峰, 孙鹏, 易重桂2018物理学报67 047101]
[20] Gao X Q, Guo Z Y, Cao D X, Zhang Y F, Sun H Q, Deng B 2010 Acta Phys. Sin. 59 341408(in Chinese)[高小奇, 郭志友, 曹东兴, 张宇飞, 孙慧卿, 邓贝2010物理学报59 341408]
[21] Almeida Jr E de, Brito Mota F de, Castilho C de, Kakanakova-Georgieva A, Gueorguiev G K 2012 Eur. Phys. J. B 85 48
[22] Jia Y P, Shi Z M, Hou W T, Zang H, Jiang K, Chen Y, Zhang S L, Qi Z B, Wu T, Sun X J, Li D B 2020 npj 2D Mater. Appl. 4 31
[23] Gürbüz E, Cahangirov S, Durgun E, Ciraci S 2017 Phys. Rev. B 96 205427
[24] Zhou R, Liang H P, Duan Y F, Wei S H 2023 J. Phys. Chem. Lett. 14 737
[25] Sheng X L, Yan Q B, Ye F, Zheng Q R, Su G 2011 Phys. Rev. Lett. 106 155703
[26] Zhang J, Wang R, Zhu X, Pan A, Han C, Li X, Zhao D, Ma C, Wang Q, Su H, Niu C 2017 Nat. Commun. 8 683
[27] Liu W H, Luo J W, Li S, Wang L W 2020 Phys. Rev. B 102 184308
[28] Liang H P, Zhong H Z, Huang S, Duan Y F 2021 J. Phys. Chem. Lett. 12 10975
[29] Oganov A R, Ma Y, Lyahov A O, Valle M, Gatti C 2010 Rev. Mineral. Geochem. 71 271
[30] Oganov A R, Lyahov A O, Valle M 2011 Acc. Chem. Res. 44 227
[31] Oganov A R, Class C W 2006 J. Chem. Phys. 124 244704
[32] Hohenberg P, Kohn W 1964 Phys. Rev. 136 B864
[33] Kohn W, Sham L J 1965 Phys. Rev. 140 A1133
[34] Kresse H, Hafner J 1993 Phys. Rev. B 47 558
[35] Kresse H, Hafner J 1994 Phys. Rev. B 49 14251
[36] Kresse H, Furthmüller J 1996 Phys. Rev. B 54 11169
[37] Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[38] Heyd J, Scueria G E, Ernzerhof M 2003 J. Chem. Phys. 118 8207
[39] Jia W, Fu J, Cao Z, Wang L, Chi X, Gao W, Wang L W 2013 Comput. Phys. Commun. 251 102
[40] Jia W, Cao Z, Wang L, Fu J, Chi X, Gao W, Wang L W 2013 Comput. Phys. Commun. 184 9
[41] Atsush T, Isa T 2015 Scripta Mater. 108 1
[42] Li W, Carrete J, Katcho N A, Mingo N 2014 Comput. Phys. Commun. 185 1747
[43] Homayoun J, Bahram A R, Mahdi F 2018 Solid State Commun. 282 21
[44] Cheng Z F, Zheng R L 2016 Acta Phys. Sin. 65 104701(in Chinese)[程正富, 郑瑞伦2016物理学报65 104701]
[45] Lv F, Liang H P, Duan Y F 2023 Phys. Rev. B 107 045422
[46] Koh Y R, Mamun A, Bin Hoque M S, Liu Z Y, Bai T Y, Hussain K, Liao M E, Li R Y, Gaskins J T, Giri A, Tomko J, Braun J L, Gaevski M, Lee E, Yates L, Goorsky M S, Luo T F, Khan A, Graham S, Hopkins P E 2020 ACS Appl. Mater. Interfaces 12 29443
[47] Mortazavi B, Shahrokhi M, Raeisi M, Zhuang X, Pereira L F C, Rabczuk T 2019 Carbon 149 733
[48] Lindsay L, Broido D A, Mingo N 2010 Phys. Rev. B 82 115427
计量
- 文章访问数: 212
- PDF下载量: 19
- 被引次数: 0
下载:
