水分子对CuHCF阴极中的金属离子扩散的影响
1School of Physical Science and Technology, Ningbo University, Ningbo 315211, China. guxiao@nbu.edu.cn.
Physical chemistry chemical physics : PCCP
|July 31, 2024
概括
水分子显著阻碍了离子扩散在离子电池的铜六化酸盐 (CuHCF) 阴极. 化Li+和Na+离子面临着大幅增加的扩散障碍,影响电池性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 计算化学计算化学
背景情况:
- 普鲁士蓝色类似物是离子电池的有希望的阴极材料.
- 水分子对这些电池材料的电化学性能产生负面影响.
研究的目的:
- 为了研究水分子对铜六酸盐 (CuHCF) 阴极中离子扩散的影响.
- 了解在扩散过程中水与离子相互作用的机制.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 模拟集中在CuHCF中的离子扩散,有和没有水分子.
主要成果:
- +和Na+离子在CuHCF间位空隙中形成水合离子.
- 由于固态阻碍,K+离子不会形成水合离子.
- 当携带水分子时,Li+和Na+的扩散障碍显著增加.
- 插入的水分子的数量直接影响Li+和Na+离子扩散.
结论:
- 水分子对CuHCF阴极中的离子扩散构成重大挑战.
- 水效应是离子特异性的,对Li+和Na+的影响比K+更大.
- 控制水含量对于优化电池中的普鲁士蓝模拟阴极性能至关重要.
相关概念视频
Alkali Metals
19.2K
Group 1 elements are soft and shiny metallic solids. They are malleable, ductile, and good conductors of heat and electricity. The melting points of the alkali metals are unusually low for metals and decrease going down the group, while the density increases going down the group with the exception of potassium (Table 1).
Table 1: Properties of the alkali metals
Table 1: Properties of the alkali metals
19.2K
Ions as Acids and Bases
23.7K
Salts with Acidic Ions
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
23.7K
Formation of Complex Ions
23.6K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
23.6K
Common Ion Effect
41.4K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
41.4K
Aqueous Solutions and Heats of Hydration
14.6K
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
14.6K
Factors Affecting Activity Coefficient
783
The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size.
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
783


