在室温附近具有巨大的电热强度的柔软矿型抗铁电
Maofan Li1,2, Shiguo Han1,3, Yi Liu1,3
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China.
Journal of the American Chemical Society
|November 23, 2020
概括
研究人员开发了一种新的软抗铁电材料 (异) 2CsPb2Br7,用于高效的固态制冷. 这种材料在低电场下表现出巨大的室温电热效应,超过现有的软聚合物.
科学领域:
- 材料科学
- 固态物理
- 热力学
背景情况:
- 抗铁电材料显示出通过电热 (EC) 效应进行固态冷却的前景.
- 由于高电场要求,现有的无机氧化物和有机聚合物具有有限的EC强度.
- 在较低的电场上开发具有强烈EC效应的软反铁电是一种重大挑战.
研究的目的:
- 合成和描述一种新的矿类软抗铁电材料.
- 为了研究其电热性质的潜在固态制冷应用.
- 探索新材料中增强EC强度的基本机制.
主要方法:
- 使用混合电离合金制造矿类型的反铁电 (异) 2CsPb2Br7.
- 测量了极化与电场歇斯底里循环以确认铁电和反铁电顺序.
- 在不同的电场和温度下评估了电热强度和变化.
主要成果:
- 这种新材料在321K和350K的温度下表现出多个相变.
- 在13kV/cm的低电场下,近室温EC强度达到了15.4 Km MV-1.
- 该材料显示了约4.1JK-1kg-1的显著EC变化和约2K的温度变化.
结论:
- 开发的 (异胺) 2CsPb2Br7是一种有前途的软反铁电,用于高效固态制冷.
- 它在混合矿中的前所未有的室温EC强度为材料发现开辟了新的途径.
- 由有机间隔器重定向和Cs+离子转移驱动的低临界场对其性能至关重要.
更多相关视频
08:00Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
11.4K
11:11Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation
Published on: May 2, 2016
11.4K
相关概念视频
Ferromagnetism
2.8K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.8K
Types Of Superconductors
1.4K
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...
1.4K
Superconductor
1.5K
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...
1.5K
Molecular and Ionic Solids
19.3K
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
19.3K
Paramagnetism
2.9K
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
2.9K
