Structural characteristics and sodium penetration behaviors in anthracite cathodes: a combination study using Monte Carlo and molecular dynamics simulations
Structural characteristics and sodium penetration behaviors in anthracite cathodes: a combination study using Monte Carlo and molecular dynamics simulations
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无烟煤阴极的结构特征和钠渗透行为：蒙特卡罗和分子动力学模拟的组合研究
DOI：
10.1007/s42823-019-00094-0
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发表时间：
2019-11
期刊：
影响因子：
4.5
通讯作者：
Xiao Jin
中科院分区：
文献类型：
--
作者：
Li Jie;Li Jiaqi;Zhang Hongliang;Li Tianshuang;Xiao Jin
在铝电解中，钠渗透到碳阴极被认为是电池故障和效率损失的主要原因，但详细机制仍不清楚。由于材料的宏观特性取决于微观结构，因此构建了无烟煤阴极的大规模原子模型来表示几个重要的结构特征。结合蒙特卡罗和分子动力学模拟，分别研究了钠的吸附和扩散行为。结果表明，钠吸附主要发生在10-19 Å范围内的较大微孔中，同时符合I型Langmuir吸附模型。发现钠优先吸附在具有 5 或 7 元环或杂原子（尤其是氧）周围的拱形结构中。此外，钠在碳基质中的运动主要依赖于连续扩散运动，而大多数钠颗粒往往被捕获在移动性较小的空隙中。计算得出的传输扩散系数等于 6.132 × 10−10m2/s，与实验结果非常吻合。这项基础研究将有助于理解钠渗透机制和未来阴极产业的优化。
In aluminum electrolysis, sodium penetration into carbon cathodes is considered as the main cause of cell failure and efficiency loss, but the detailed mechanism is still not definitely clear. Since the macroscopic properties of material depend on the microscopic structures, a large-scale atomistic model of anthracite cathodes was constructed to represent several important structural characteristics. Combined with Monte Carlo and molecular dynamics simulations, the adsorption and diffusion behaviors of sodium were investigated, respectively. The results suggest that sodium adsorption mainly occurs in the larger micro-pores with the range of 10–19 Å, while it accords well with to type-I Langmuir adsorption model. The sodium is found to be preferentially adsorbed in arch-like structures with 5- or 7-membered rings or around heteroatom, especially oxygen. Moreover, the movements of sodium through carbon matrix mainly depend on the continuous diffusive motion while most sodium particles tend to be trapped in voids with small mobility. The calculated transport diffusion coefficient is equal to 6.132 × 10−10m2/s, which is in outstanding agreement with experimental results. This fundamental research would contribute to the understanding of sodium penetration mechanism and the optimization of cathode industry in the future.
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DOI：
10.1016/j.msea.2017.01.061
发表时间：
2017-02
影响因子：
6.4
作者：
Wei Wang-;Weijie Chen;W. Gu
通讯作者：
Wei Wang-;Weijie Chen;W. Gu
DOI：
--
发表时间：
1993-08
期刊：
arXiv: High Energy Physics - Phenomenology
影响因子：
--
作者：
J. Govaerts
通讯作者：
J. Govaerts
DOI：
--
发表时间：
1997
期刊：
--
影响因子：
--
作者：
T. Naas
通讯作者：
T. Naas
影响因子：
8.6
作者：
Dubbeldam, D;Calero, S;Smit, B
通讯作者：
Smit, B
影响因子：
5.3
作者：
Atria, JV;Rusinko, F;Schobert, HH
通讯作者：
Schobert, HH