Ji Hua, Ren Keliang, Yang Jia, Zhang Yating, Wang Guan
School of Physics and Electronic-Electrical Engineering, Ningxia University, Yinchuan, China.
School of Mechanical Engineering, Ningxia University, Yinchuan, China.
Front Chem. 2022 Jun 29;10:930900. doi: 10.3389/fchem.2022.930900. eCollection 2022.
Aiming at the performance degradation of lithium-ion batteries due to shell corrosion, the doping of alloy elements Zn, Mg and Cu on Al (111) surface and the effect on oxidation reaction of Al (111) surface were studied by the first-principles calculation method. The results show that Zn, Mg and Cu atoms stably combine with Al atoms, and the surface smoothness is slightly different due to their different radii and electronegativity. The dissociative adsorption of O molecules is related to the surface doping atoms and O coverage, while the electron tunneling of underlying metal promotes O adsorption on the surface. As O coverage increases, the O atoms adsorbed on the hcp site gradually migrate to the subsurface layer. Zn, Mg, Cu and vacancy defect hinder the migration of the surrounding O atoms to subsurface layer, resulting in different structures and thicknesses of the oxide film near the doped atoms. At the same time, Zn, Mg, and Cu atoms differ in their ability to gain or lose electrons compared with Al atoms, resulting in their different positions on the surface. In addition, the surface work function rises with the increase of O coverage, and Zn and Cu atoms make the work function increase faster. Finally, according to the research results, it can be inferred that Zn and Mg are the unfavorable factors for the oxidation reaction of Al surface.
针对锂离子电池因外壳腐蚀导致的性能退化问题,采用第一性原理计算方法研究了合金元素Zn、Mg和Cu在Al(111)表面的掺杂情况以及对Al(111)表面氧化反应的影响。结果表明,Zn、Mg和Cu原子与Al原子稳定结合,由于它们的半径和电负性不同,表面平整度略有差异。O分子的解离吸附与表面掺杂原子和O覆盖率有关,而底层金属的电子隧穿促进了O在表面的吸附。随着O覆盖率的增加,吸附在hcp位点上的O原子逐渐迁移到次表层。Zn、Mg、Cu和空位缺陷阻碍了周围O原子向次表层的迁移,导致掺杂原子附近氧化膜的结构和厚度不同。同时,Zn、Mg和Cu原子与Al原子相比得失电子能力不同,导致它们在表面的位置不同。此外,表面功函数随O覆盖率的增加而升高,Zn和Cu原子使功函数增加得更快。最后,根据研究结果可以推断,Zn和Mg是Al表面氧化反应的不利因素。