文献类型：期刊文献

英文题名：Machine-Learning-Driven Simulations on Microstructure and Thermophysical Properties of MgCl2-KCl Eutectic

作者：Liang, Wenshuo[1,2];Lu, Guimin[1,2];Yu, Jianguo[1,2]

机构：[1]East China Univ Sci & Technol, Sch Resources & Environm Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, Shanghai 200237, Peoples R China

年份：2021

卷号：13

期号：3

起止页码：4034

外文期刊名：ACS APPLIED MATERIALS & INTERFACES

收录：;EI(收录号：20210509846366);WOS:【SCI-EXPANDED(收录号:WOS:000614062400050)】；

基金：The authors acknowledge the financial support provided by the National Natural Science Foundation of China (Grant U20A20147). W.L. thanks Haiou Ni and Bo Yang for their help in installing the software. W.L. also thanks Gechuanqi Pan for inspired discussions on MD simulations on this system.

语种：英文

外文关键词：MgCl2-KCl eutectic; microstructure; thermophysical properties; machine learning; deep potential

摘要：Theoretical studies on the MgCl2-KCl eutectic heavily rely on ab initio calculations based on density functional theory (DFT). However, neither large-scale nor long-time calculations are feasible in the framework of the ab initio method, which makes it challenging to accurately predict some properties. To address this issue, a scheme based on ab initio calculation, deep neural networks, and machine learning is introduced. By training on high-quality data sets generated by ab initio calculations, a deep potential (DP) is constructed to describe the interaction between atoms. This work shows that the DP enables higher efficiency and similar accuracy relative to DFT. By performing molecular dynamics simulations with DP, the microstructure and thermophysical properties of the MgCl2-KCl eutectic (32:68 mol %) are investigated. The structural evolution with temperature is analyzed through partial radial distribution functions, coordination numbers, angular distribution functions, and structural factors. Meanwhile, the estimated thermophysical properties are discussed, including density, thermal expansion coefficient, shear viscosity, self-diffusion coefficient, and specific heat capacity. It reveals that the Mg2+ ions in this system have a distorted tetrahedral geometry rather than an octahedral one (with vacancies). The microstructure of the MgCl2-KCl eutectic shows the feature of medium-range order, and this feature will be enhanced at a higher temperature. All predicted thermophysical properties are in good agreement with the experimental results. The hydrodynamic radius determined from the shear viscosity and self-diffusion coefficient shows that the Me ions have a strong local structure and diffuse as if with an intact coordination shell. Overall, this work provides a thorough understanding of the microstructure and enriches the data of the thermophysical properties of the MgCl2-KCl eutectic.