Wenhui Wan , YiRan Peng , Yanfeng Ge , Botao Fu , Yong Liu
{"title":"单层氧化 GeO 中稳健的面内铁电性、高空穴迁移率和低热导率:第一原理研究","authors":"Wenhui Wan , YiRan Peng , Yanfeng Ge , Botao Fu , Yong Liu","doi":"10.1016/j.physe.2024.115997","DOIUrl":null,"url":null,"abstract":"<div><p>Motivated by the experimental advancements in 2D crystalline germanium oxides, we investigated the electronic and transport properties of GeO and GeO<sub>2</sub> monolayers (MLs) using first-principles calculations. GeO ML exhibits an in-plane ferroelectricity until the melting point of 1100 K. Compressive strain facilitates polarization reversion by lowering the ferroelectric transition barrier. The band edges meet the requirements for photocatalytic water splitting across a wide variety of strains. Meanwhile, GeO ML has a high hole mobility of 4854 cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>/V<span><math><mi>⋅</mi></math></span>s along the <span><math><mi>y</mi></math></span>-axis, owing to its low deformation potential constant. The large difference in hole and electron mobility promotes electron–hole separation. In addition, GeO ML has a low thermal conductivity of <span><math><msub><mrow><mi>κ</mi></mrow><mrow><mi>x</mi></mrow></msub></math></span> = 3.37 W/mK and <span><math><msub><mrow><mi>κ</mi></mrow><mrow><mi>y</mi></mrow></msub></math></span> = 12.53 W/mK at 300 K, due to the strong anharmonicity caused by lone-pair electrons. In contrast, GeO<sub>2</sub> ML has an isotropic electron mobility of 382 cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>/V<span><math><mi>⋅</mi></math></span>s and an <span><math><mi>κ</mi></math></span> of 22.60 W/mK at 300 K. At last, we discussed the probable reaction to grow 2D GeO crystal and calculated the Raman intensity to distinguish it in future experiments. Our results show that 2D GeO has potential applications in ferroelectrics, thermoelectrics, and water splitting.</p></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":null,"pages":null},"PeriodicalIF":2.9000,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Robust in-plane ferroelectricity, high hole mobility, and low thermal conductivity in GeO monolayer: A first-principles study\",\"authors\":\"Wenhui Wan , YiRan Peng , Yanfeng Ge , Botao Fu , Yong Liu\",\"doi\":\"10.1016/j.physe.2024.115997\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Motivated by the experimental advancements in 2D crystalline germanium oxides, we investigated the electronic and transport properties of GeO and GeO<sub>2</sub> monolayers (MLs) using first-principles calculations. GeO ML exhibits an in-plane ferroelectricity until the melting point of 1100 K. Compressive strain facilitates polarization reversion by lowering the ferroelectric transition barrier. The band edges meet the requirements for photocatalytic water splitting across a wide variety of strains. Meanwhile, GeO ML has a high hole mobility of 4854 cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>/V<span><math><mi>⋅</mi></math></span>s along the <span><math><mi>y</mi></math></span>-axis, owing to its low deformation potential constant. The large difference in hole and electron mobility promotes electron–hole separation. In addition, GeO ML has a low thermal conductivity of <span><math><msub><mrow><mi>κ</mi></mrow><mrow><mi>x</mi></mrow></msub></math></span> = 3.37 W/mK and <span><math><msub><mrow><mi>κ</mi></mrow><mrow><mi>y</mi></mrow></msub></math></span> = 12.53 W/mK at 300 K, due to the strong anharmonicity caused by lone-pair electrons. In contrast, GeO<sub>2</sub> ML has an isotropic electron mobility of 382 cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>/V<span><math><mi>⋅</mi></math></span>s and an <span><math><mi>κ</mi></math></span> of 22.60 W/mK at 300 K. At last, we discussed the probable reaction to grow 2D GeO crystal and calculated the Raman intensity to distinguish it in future experiments. 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引用次数: 0
摘要
在二维晶体锗氧化物实验进展的推动下,我们利用第一原理计算研究了 GeO 和 GeO 单层 (ML) 的电子和传输特性。GeO ML 在 1100 K 熔点之前一直表现出平面内铁电性。在各种应变下,带边都能满足光催化水分离的要求。同时,由于 GeO ML 的形变位常数较低,其沿 - 轴的空穴迁移率高达 4854 cm/Vs。空穴和电子迁移率的巨大差异促进了电子-空穴分离。此外,GeO ML 的热导率较低,在 300 K 时为 = 3.37 W/mK 和 = 12.53 W/mK,这是由于孤对电子造成的强非谐性。最后,我们讨论了生长二维 GeO 晶体的可能反应,并计算了拉曼强度,以便在今后的实验中加以区分。我们的研究结果表明,二维 GeO 在铁电、热电和水分离方面具有潜在的应用前景。
Robust in-plane ferroelectricity, high hole mobility, and low thermal conductivity in GeO monolayer: A first-principles study
Motivated by the experimental advancements in 2D crystalline germanium oxides, we investigated the electronic and transport properties of GeO and GeO2 monolayers (MLs) using first-principles calculations. GeO ML exhibits an in-plane ferroelectricity until the melting point of 1100 K. Compressive strain facilitates polarization reversion by lowering the ferroelectric transition barrier. The band edges meet the requirements for photocatalytic water splitting across a wide variety of strains. Meanwhile, GeO ML has a high hole mobility of 4854 cm/Vs along the -axis, owing to its low deformation potential constant. The large difference in hole and electron mobility promotes electron–hole separation. In addition, GeO ML has a low thermal conductivity of = 3.37 W/mK and = 12.53 W/mK at 300 K, due to the strong anharmonicity caused by lone-pair electrons. In contrast, GeO2 ML has an isotropic electron mobility of 382 cm/Vs and an of 22.60 W/mK at 300 K. At last, we discussed the probable reaction to grow 2D GeO crystal and calculated the Raman intensity to distinguish it in future experiments. Our results show that 2D GeO has potential applications in ferroelectrics, thermoelectrics, and water splitting.
期刊介绍:
Physica E: Low-dimensional systems and nanostructures contains papers and invited review articles on the fundamental and applied aspects of physics in low-dimensional electron systems, in semiconductor heterostructures, oxide interfaces, quantum wells and superlattices, quantum wires and dots, novel quantum states of matter such as topological insulators, and Weyl semimetals.
Both theoretical and experimental contributions are invited. Topics suitable for publication in this journal include spin related phenomena, optical and transport properties, many-body effects, integer and fractional quantum Hall effects, quantum spin Hall effect, single electron effects and devices, Majorana fermions, and other novel phenomena.
Keywords:
• topological insulators/superconductors, majorana fermions, Wyel semimetals;
• quantum and neuromorphic computing/quantum information physics and devices based on low dimensional systems;
• layered superconductivity, low dimensional systems with superconducting proximity effect;
• 2D materials such as transition metal dichalcogenides;
• oxide heterostructures including ZnO, SrTiO3 etc;
• carbon nanostructures (graphene, carbon nanotubes, diamond NV center, etc.)
• quantum wells and superlattices;
• quantum Hall effect, quantum spin Hall effect, quantum anomalous Hall effect;
• optical- and phonons-related phenomena;
• magnetic-semiconductor structures;
• charge/spin-, magnon-, skyrmion-, Cooper pair- and majorana fermion- transport and tunneling;
• ultra-fast nonlinear optical phenomena;
• novel devices and applications (such as high performance sensor, solar cell, etc);
• novel growth and fabrication techniques for nanostructures