Effect of Crystal Orientation of Cu Current Collectors on Cycling Stability of Li Metal Anodes
Effect of Crystal Orientation of Cu Current Collectors on Cycling Stability of Li Metal Anodes
复制标题
铜集流体晶体取向对锂金属负极循环稳定性的影响
DOI：
10.1021/acsami.9b22157
复制
发表时间：
2020
影响因子：
9.5
通讯作者：
Ujihara Toru
中科院分区：
文献类型：
--
作者：
Ishikawa Kohei;Harada Shunta;Tagawa Miho;Ujihara Toru
锂金属阳极由于界面不稳定，库仑效率较低。人们提出了许多方法来解决这个问题，但很少有人关注锂阳极的电流收集器。在本研究中，我们研究了单晶铜(111)、(101)、(001)和多晶铜集电体对锂阳极循环稳定性的晶体取向依赖性。循环伏安(CV)和交流阻抗谱(EIS)结果表明，(111)和(001)晶面具有较高的电流效率和较低的界面电阻，而(101)晶面和多晶铜的循环性能较低。X射线光电子能谱(XPS)和俄歇电子能谱(AES)分析表明，固体电解质界面(SEI)的厚度随铜晶体取向的不同而不同，且单晶Cu(111)上的SEI最薄。这一趋势可以用铜表面能的取向依赖性来解释，这与表面的化学活性相对应。我们的结果强调了在锂金属阳极界面工程中考虑铜的取向的重要性。
Li metal anodes are plagued by low coulombic efficiency due to their interfacial instability. Many approaches were proposed to cope with this problem; however, little attention has been given to the current collector of Li anodes. In this study, we investigate the crystal orientation dependence of the cycling stability of Li anodes on single-crystal Cu(111), (101), and (001) and polycrystalline Cu current collectors. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) show that (111) and (001) achieved high current efficiency and low interfacial resistance, while (101) and polycrystalline Cu exhibited low cyclabilities. X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES) analysis revealed that the thickness of the solid electrolyte interphase (SEI) varies with the Cu crystal orientation, and the SEI is the thinnest on the single-crystal Cu(111). This tendency can be explained by the orientation dependence of the surface energy of Cu, which corresponds to the chemical activity of the surfaces. Our result advocates the importance of considering Cu orientation for interfacial engineering of Li metal anodes.