通过非平衡分子动力学和密度函数理论探索石墨电极中的离子相互作用
Ding Shen1, ZhaoQi Ren1, Shuang Wei1
1College of Material Science and Engineering, Liaoning Technical University, Fuxin 123000, China. shending028@163.com.
Physical chemistry chemical physics : PCCP
|November 6, 2024
概括
选择正确的电位函数是模拟石墨中离子行为的关键. 这项研究发现,AIREBO和Tersoff潜能准确地模拟了不同的离子排列,有助于电池设计.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 电化学 电化学 电化学
背景情况:
- 在石墨中精确模拟离子动态对于先进的电池开发至关重要.
- 潜在的函数选择对分子动力学 (MD) 模拟的忠实性产生了关键影响,用于介质和扩散过程.
研究的目的:
- 评估不同潜在功能的适用性,以模拟石墨中的离子行为.
- 提供关于石墨电极内离子间隙和扩散动力学的见解.
- 为优化离子电池性能建立理论基础.
主要方法:
- 采用混合方法,结合非平衡分子动力学 (NEMD) 和密度功能理论 (DFT).
- 评估了AIREBO潜在函数,用于石墨层之间有序的离子运动.
- 评估了石墨层内折叠的离子结构的特索夫电位函数.
主要成果:
- AIREBO潜力模型准确地订购了离子运动,与Rüdorff-Hofmann (R-H) 和Daumas-Hérold (D-H) 模型保持一致.
- 特索夫潜力适用于局部离子结构,与局部域模型相一致.
- 增加离子度会降低电压,模和Li6的抗拉强度.
- 石墨中的离子扩散系数范围广泛,从10~6到10~16厘米~2~1厘米.
结论:
- 潜在功能的选择 (AIREBO与Tersoff) 取决于石墨结构内的特定离子排列.
- 模拟结果为理解离子间隙和扩散机制提供了一个理论框架.
- 这些发现可以指导高性能离子电池的设计和优化.
相关概念视频
Molecular Orbital Theory II
19.0K
Molecular Orbital Energy Diagrams
19.0K
Ionic Bonding and Electron Transfer
41.2K
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
41.2K
Network Covalent Solids
13.4K
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...
13.4K
Electrogravimetric Analysis: Overview
208
Electrogravimetric analysis measures the weight of an analyte deposited electrolytically onto a suitable working electrode. This method involves applying a potential to a pre-weighed electrode submerged in a solution, which results in the desired substance being deposited through reduction at the cathode or oxidation at the anode. The electrode's weight is recorded after deposition, and the difference in weight gives the analyte's weight in the solution.
To test the completeness of the...
To test the completeness of the...
208
Trends in Lattice Energy: Ion Size and Charge
23.7K
An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure of the strength of this attraction. The lattice energy (ΔHlattice) of an ionic compound is defined as the energy required to separate one mole of the solid into its component gaseous ions. For the ionic solid sodium chloride, the lattice energy is the enthalpy change of the process:
23.7K


