Using the density functional theory (DFT), first-principles computations were performed to investigate the intercalation site, phase transformation, electronic properties, and migration energy barrier of Li and Mg atoms in V₂O₅ to thoroughly illuminate the phase transformation and microscopic interaction as well as the migration mechanism of Li and Mg in V₂O₅. It is found that Li and Mg atoms prefer to locate at the site that is above, near the center of the quadrilateral composed of four V atoms. With the increase of the intercalation concentration (0 ≤ x ≤ 1), V₂O₅ undergoes a structural transformation from α-phase to ε-phase and δ-phase. Compared with ε-M_0.5V₂O₅ (M = Li/Mg), the electronic conductivity of δ-MV₂O₅ (M = Li/Mg) is declined. On the basis of diffusion kinetics, Mg exhibits more difficulty in inserting and extracting in V₂O₅ than Li. This study can be useful for the further application of V₂O₅ in Mg ion batteries.

中文翻译：

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锂和镁可充电电池中V ₂ O ₅电极的相变和扩散动力学：第一性原理研究

使用密度泛函理论（DFT），进行了第一性原理计算，以研究Li和Mg原子在V ₂ O _5中的嵌入位置，相变，电子性质和迁移能垒，以彻底阐明相变和微观相互作用。以及Li和Mg在V ₂ O _5中的迁移机理。发现Li和Mg原子更喜欢位于由四个V原子组成的四边形的中心上方的位置附近。与层夹浓度（0≤的增加X ≤1），V ₂ ö ₅经历了从α相到ε相和δ相的结构转变。与ε-M相比_0.5 V ₂ ø ₅（M =锂/镁），δ-MV的电子传导性₂ ø ₅（M =锂/镁）的下降。根据扩散动力学，Mg在V ₂ O ₅中的插入和萃取比Li困难得多。这项研究对于镁离子电池中V ₂ O ₅的进一步应用可能是有用的。