压力对单层Janus MoSSe材料的热电性能的影响,这些材料具有不同的原生空位缺陷
Yuan Shang1, Xiaopeng Pan2, Yanxing Jia2
1School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China. mengtaosun@ustb.edu.cn.
Nanoscale
|May 21, 2025
概括
施加压力可以提高2D材料的热电性能,例如Janus MoSSe. 空位缺陷改变了这一效应,硫空位降低了性能,空位表现出复杂的压力依赖行为.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 二维 (2D) 材料具有独特的电子和热性能.
- 空位缺陷显著影响二维材料的热电性能.
- 了解压力效应对于优化热电设备至关重要.
研究的目的:
- 为了研究外部压力对单层Janus MoSSe的热电性能的影响.
- 在不同压力下分析硫 (VS) 和 (VSe) 空缺缺陷的不同影响.
- 阐明控制压力诱导热电性质变化的基本机制.
主要方法:
- 使用了第一原则计算.
- 使用的非平衡格林的功能形式主义 (NEGF).
- 模拟的单层Janus MoSSe在液压下具有和没有VS和VSe缺陷.
主要成果:
- 压力通过增加功率因子 (PF) 来增强原始Janus MoSSe中的热电功率 (ZT),几乎使ZT在300 K时翻了一番.
- VS空缺缺陷导致ZT因压力诱导下降,由于PF降低和导热率增加.
- VSe空缺缺陷表现出一种非单调的ZT对压力的反应,在较低的压力下 (0-5 GPa) 增加,在较高的压力下 (7.5 GPa) 减少.
结论:
- 压力是优化二维材料热电性能的一个可行的调整参数.
- 空缺缺陷的存在和类型极大地改变了材料对压力的反应.
- 结果突显了Janus MoSSe中缺陷,压力和热电传输之间的复杂相互作用.
相关概念视频
Biasing of Metal-Semiconductor Junctions
183
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
183
Joule-Thomson Effect
2.6K
The Joule-Thomson effect, also known as the Joule-Kelvin effect, describes the temperature change of a fluid when it is forced through a valve or porous plug while keeping it in a thermally insulated environment. This experiment is called a throttling process. This is an important effect widely used in refrigeration and the liquefaction of gases.
This experiment forces high-pressure gas through a throttle valve or a porous plug to a lower-pressure region. The gas expands as it passes through to...
This experiment forces high-pressure gas through a throttle valve or a porous plug to a lower-pressure region. The gas expands as it passes through to...
2.6K
Thermodynamic Potentials
749
Thermodynamic potentials are state functions that are extremely useful in analyzing a thermodynamic system. They have dimensions of energy. The four important thermodynamic potentials are internal energy, enthalpy, Helmholtz free energy, and Gibbs free energy. These thermodynamic potentials can be expressed using two of the following variables: pressure, volume, temperature, and entropy. These two variables are expressed as the rate of change of the thermodynamic potential with respect to other...
749
Schottky Barrier Diode
276
Schottky barrier diodes are specialized semiconductor devices characterized by their unique construction. This construction involves combining a metal layer with a moderately doped n-type semiconductor material. This combination leads to the formation of a Schottky barrier, a pivotal element that defines the diode's operational characteristics. The core functionality of Schottky barrier diodes is their capacity to allow current to flow in only one direction due to their distinctive...
276
Metal-Semiconductor Junctions
264
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
264
MOSFET: Enhancement Mode
256
Enhancement-mode MOSFETs are pivotal components in electronics, distinguished by their capacity to act as highly efficient switches. They are part of the larger family of metal-oxide Semiconductor Field-Effect Transistors (MOSFETs). They are available in two types: p-channel and n-channel, each tailored to specific polarity operations.
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
256


