相关实验视频
Updated: Oct 22, 2025

08:45
Fabrication of Spatially Confined Complex Oxides
Published on: July 1, 2013
9.8K
在模块化无机材料中具有低导热性,具有粘合异性和不匹配
Quinn D Gibson1, Tianqi Zhao2, Luke M Daniels1
1Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, UK.
概括
研究人员通过控制声子行为, 实现了分层材料的超低导热率. 这一材料科学突破为先进的热管理应用提供了潜力.
科学领域:
- 材料科学
- 凝聚物质物理学
- 固态化学
背景情况:
- 晶体材料具有由声子分散决定的内在最小导热极限.
- 控制声子传输对于开发具有定制热性质的材料至关重要.
研究的目的:
- 探索抑制层级材料中纵向和横向声子对热传输的策略.
- 通过在超级网格结构中的化学工程接口来实现极低的导热率.
主要方法:
- 使用补充策略以准纵向和横向的语音模式.
- 合成和特征分层材料,包括BiOCl,Bi2O2Se和超级晶格Bi4O4SeCl2.
- 研究了化学接口安排和振动模式的修改之间的关系.
主要成果:
- 证明 BiOCl 和 Bi2O2Se 能够有效地抑制纵向和横向的声子.
- 在堆叠方向上,在Bi4O4SeCl2中达到0.1W/K·m的非常低的室温导热率.
- 这个值与空气的导热率相当,表明有显著的声子散射.
结论:
- 对不同接口的空间布局进行化学控制可以协同修改振动模式.
- 这种方法可以显著降低层状晶体材料的导热率.
- 这些发现为设计具有超低导热率的材料开辟了新途径.
更多相关视频
相关概念视频
Bonding in Metals
49.3K
Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Drüde called the “Electron Sea Model”.
49.3K
Molecular and Ionic Solids
18.6K
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...
18.6K
Types of Chemical Bonds
84.4K
Chemical bonding theories were pioneered by American chemist Gilbert N. Lewis. He developed a model called the Lewis model to explain the type and formation of different bonds. Chemical bonding is central to chemistry; it explains how atoms or ions bond together to form molecules. It explains why some bonds are strong and others are weak, or why one carbon bonds with two oxygens and not three; why water is H2O and not H4O.
84.4K
Network Covalent Solids
15.2K
Network covalent solids contain a three-dimensional network of covalently bonded atoms as found in the crystal structures of nonmetals like diamond, graphite, silicon, and some covalent compounds, such as silicon dioxide (sand) and silicon carbide (carborundum, the abrasive on sandpaper). Many minerals have networks of covalent bonds.
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
15.2K
Theory of Metallic Conduction
1.5K
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,...
1.5K
Bonding and Strength of Aggregate
274
The bond between aggregate particles and the cement matrix is significantly influenced by the shape and surface texture of the aggregates. High-strength concretes benefit from a rougher texture, which leads to stronger bonding due to greater adhesion. Angular aggregates with larger surface areas also enhance this bond. The bonding quality, however, is complex to assess as no universally accepted test exists. Good bonding is indicated when a crushed concrete specimen shows some aggregate...
274

