论文标题
超薄金属阳极的表面工程，可实现高性能Zn-Ion电池
Surface engineering for ultrathin metal anodes enabling high-performance Zn-ion batteries
论文作者
论文摘要
在可再生能源存储和网格存储中，Zn金属电池被认为是一种有希望的替代储能技术。众所周知，锌金属阳极的表面方向对于锌金属电池的可逆性至关重要。在此，通过在ZnSO4水溶液中添加（DMSO）电解质添加剂，将（101）面向的薄Zn金属阳极（向下至2μm）在Cu表面上进行电沉积。扫描电子显微镜（SEM）观察表明形成了扁平露台状的紧凑型（101）面向的表面。 Insitu光学观察证实，（101）面向的表面可以可逆地镀板和剥离。 DFT计算揭示了Zn-（101）表面成核和生长的两种机制：（1）与Zn（002）// Cu（001）相比，Zn（101）// Cu（101）// Cu（001）的形成可以降低界面能量； （2）具有DMSO和H2O吸收的Zn（101）表面的大量重建。拉曼，XP和TOF-SIMS表征表明，在ZnCl2中添加DMSO可以促进基于ZnO的SEI在Zn金属表面上的形成，而在ZNSO4中可以通过DMSO获得OH-和S基SEI。进行了电化学测试，该测试表明，在半细胞中，（101）面向（101）面向的Zn以及相对于相同电极厚度的（002）区域的表面的较低电荷传递屏障。 Zn || V2O5全细胞进一步组装，与（5μM，3μM和2μM）的（002）-ZN相比，（101）-ZN显示了（101）-ZN的能力保持更好。我们希望这项研究能够促进对Zn金属表面晶体学方向的控制，这是对超薄Zn金属阳极的控制。
Zn metal battery has been considered a promising alternative energy storage technology in renewable energy storage and grid storage. It is well-known that the surface orientation of a Zn metal anode is vital to the reversibility of a Zn metal battery. Herein, the (101)-oriented thin Zn metal anode (down to 2 μm) is electrodeposited on a Cu surface by adding dimethyl sulfoxide (DMSO) electrolyte additive in ZnSO4 aqueous solution. Scanning electron microscope (SEM) observation indicates the formation of flat terrace-like compact (101)-oriented surfaces. Insitu optical observation confirms that the (101)-oriented surfaces can be reversibly plated and stripped. DFT calculations reveal two mechanisms for the nucleation and growth of the Zn-(101) surface: (1) formation of Zn(101)//Cu(001) could lower the interface energy as compared to Zn(002)//Cu(001); (2) large reconstruction of the Zn (101) surface with DMSO and H2O absorption. Raman, XPS, and ToF-SIMS characterizations indicate that adding DMSO in ZnCl2 could facilitate the formation of ZnO-based SEI on Zn metal surface, while OH- and S-based SEI can be obtained with DMSO in ZnSO4. The electrochemical testings are performed, which demonstrates a higher cyclability for the (101)-oriented Zn in the half cell as well as a lower charge transfer barrier with respect to the (002)-dominated surface of the same electrode thickness. Zn||V2O5 full cells are further assembled, showing better capacity retention for the (101)-Zn as compared to the (002)-Zn with the same thickness (5 μm, 3 μm, and 2 μm). We hope this study to spur further interest in the control of Zn metal surface crystallographic orientation towards ultrathin Zn metal anodes.
