盐聚合物的离子导电性:温度和盐度的联合作用
Alexandros J Tsamopoulos1, Zhen-Gang Wang1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
ACS macro letters
|February 23, 2024
概括
这项研究模拟了聚乙烯氧化物和盐的相互作用,揭示了温度和盐度如何影响运输特性. 盐度增加会提高玻璃过渡温度,并通过影响聚合物链动态来影响导电性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物电解质 聚合物电解质
- 计算化学计算化学
背景情况:
- 聚合物电解质对于先进的储能设备至关重要.
- 了解聚合物电解质中的离子运输是提高电池性能的关键.
- 聚乙烯氧化物和二三甲硫胺是固态电解质中常见的成分.
研究的目的:
- 研究温度和盐度对聚合物链动态和离子传输的联合影响.
- 开发一个预测模型,用于聚合物电解质的运输特性.
- 阐明聚合物细分移动性和离子导电性之间的关系.
主要方法:
- 使用粗粒度的分子动力学模拟.
- 模型系统包括聚乙烯氧化物和二三甲) 硫胺.
- 在不同温度和盐度下分析了输送特性,包括离子扩散性和导电性.
主要成果:
- 盐剂显著阻碍了聚合物链动态,减少了离子扩散.
- 玻璃过渡温度与盐度线性增加.
- 一个修改后的Vogel-Fulcher-Tamman方程准确地描述了聚合物扩散.
- 离子导电性受到聚合物细分移动性和盐度的影响.
结论:
- 聚合物细分流动性在确定离子导电性依赖盐度方面发挥着关键作用.
- 开发的模型提供了对优化聚合物电解质组成和操作条件的见解.
- 这些发现对于设计高性能固态电池具有重要意义.
相关概念视频
Ionic Strength: Effects on Chemical Equilibria
1.5K
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary...
In this solution, the primary...
1.5K
Ionic Strength: Overview
1.4K
The ionic strength of a solution is a quantitative way of expressing the total electrolyte concentration of a solution. This concept was first introduced in 1921 by two American physical chemists, Gilbert N. Lewis and Merle Randall, while describing the activity coefficient of strong electrolytes. During the calculation of ionic strength (I or μ), all the cations and anions are considered. However, the concentration (c) of an ion with a greater charge number (z) has a greater contribution...
1.4K
Theory 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
Electrolytes: van't Hoff Factor
33.1K
Colligative Properties of Electrolytes
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
33.1K
Electrolyte and Nonelectrolyte Solutions
63.0K
Substances that undergo either a physical or a chemical change in solution to yield ions that can conduct electricity are called electrolytes. If a substance yields ions in solution, that is, if the compound undergoes 100% dissociation, then the substance is a strong electrolyte. Complete dissociation is indicated by a single forward arrow. For example, water-soluble ionic compounds like sodium chloride dissociate into sodium cations and chloride anions in aqueous solution.
63.0K
Determining the pH of Salt Solutions
43.6K
The pH of a salt solution is determined by its component anions and cations. Salts that contain pH-neutral anions and the hydronium ion-producing cations form a solution with a pH less than 7. For example, in ammonium nitrate (NH4NO3) solution, NO3− ions do not react with water whereas NH4+ ions produce the hydronium ions resulting in the acidic solution. In contrast, salts that contain pH-neutral cations and the hydroxide ion-producing anions form a solution with a pH greater than...
43.6K


