在分散的GeTe基热电复合材料中取得的卓越成绩
Yilin Jiang1, Bin Su1, Jincheng Yu1
1State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
Nature communications
|July 13, 2024
概括
将颗粒添加到 bismuth-doped telluride (GeTe) 中,可以提高其热电性能. 这种复合材料在中温应用中取得了创纪录的优点.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- telluride (GeTe) 是一种p型热电材料,具有中温应用的潜力.
- 提高热电性能需要优化电气和热传输特性.
- 复合方法提供了一种途径,可以协同调节这些特性.
研究的目的:
- 通过一种简单的复合材料方法来提高GeTe的热电性能.
- 为了研究将颗粒纳入双化GeTe的效果.
- 了解负责绩效提升的潜在机制.
主要方法:
- 制造含有不同数量的颗粒的双化GeTe复合材料.
- 结构性,电气性和热传输性能的表征.
- 对声子散射机制和界面效应的分析.
主要成果:
- 加入颗粒显著提高了功率因子,降低了导热率.
- 在613 K的温度下,由于热不匹配引起的失位引起的声子散射,达到0.43 Wm-1K-1的最小晶格导热率.
- 由于/GeTe接口增加了Seebeck系数和功率系数 (25.4μWcm−2K−2在300K)
- 在基于GeTe的复合材料中,在613K时达到4.0×10−3K−1的创纪录的优点 (ZTmax).
结论:
- 复合方法有效地通过电气和热传输的协同调制来提高GeTe的热电性能.
- 颗粒的结合提供了一个有效的策略,用于优化基于GeTe的热电技术,用于中温应用.
- 实现的ZTmax代表了GeTe材料和中温热电系统的重大进步.
相关概念视频
01:28Types Of Superconductors
968
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...
968
01:17Theory of Metallic Conduction
1.3K
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
1.3K
01:24Superconductor
1.1K
A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a superconductor. In 1911, Heike Kamerlingh Onnes of Leiden University, a Dutch physicist, observed a relation between the temperature and the resistance of the element mercury. The mercury sample was then cooled in liquid helium to study the linear dependence of resistance on temperature. It was observed that, as the temperature decreased, the...
1.1K
01:20Types of Semiconductors
585
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
585
01:26Thermodynamic Potentials
819
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...
819