Bi Jingxuan, Zhou Zhenkai, Li Junhui, Li Boxin, Sun Xiaojie, Liu Yuhang, Wang Ke, Gao Guowei, Du Zhuzhu, Ai Wei, Huang Wei
Frontiers Science Center for Flexible Electronics & Shaanxi Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an, 710072, China.
School of Materials Science and Engineering & Institute of Flexible Electronics and Intelligent Textile, Xi'an Polytechnic University, Xi'an, 710048, China.
Angew Chem Int Ed Engl. 2024 Sep 9;63(37):e202407770. doi: 10.1002/anie.202407770. Epub 2024 Aug 9.
Magnesium metal batteries (MMBs), recognized as promising contenders for post-lithium battery technologies, face challenges such as uneven magnesium (Mg) plating and stripping behaviors, leading to uncontrollable dendrite growth and irreversible structural damage. Herein, we have developed a Mg foil featuring prominently exposed (002) facets and an architecture of nanosheet arrays (termed (002)-Mg), created through a one-step acid etching method. Specifically, the prominent exposure of Mg (002) facets, known for their inherently low surface and adsorption energies with Mg atoms, not only facilitates smooth nucleation and dense deposition but also significantly mitigates side reactions on the Mg anode. Moreover, the nanosheet arrays on the surface evenly distribute the electric field and Mg ion flux, enhancing Mg ion transfer kinetics. As a result, the fabricated (002)-Mg electrodes exhibit unprecedented long-cycle performance, lasting over 6000 h (>8 months) at a current density of 3 mA cm for a capacity of 3 mAh cm. Furthermore, the corresponding pouch cells equipped with various electrolytes and cathodes demonstrate remarkable capacity and cycling stability, highlighting the superior electrochemical compatibility of the (002)-Mg electrode. This study provides new insights into the advancement of durable MMBs by modifying the crystal structure and morphology of Mg.
镁金属电池（MMBs）被认为是锂电池技术之后很有前景的竞争者，但面临着诸如镁（Mg）电镀和剥离行为不均匀等挑战，导致枝晶生长失控和不可逆的结构损伤。在此，我们通过一步酸蚀法开发了一种具有显著暴露（002）面和纳米片阵列结构的镁箔（称为（002）-Mg）。具体而言，Mg（002）面的显著暴露，因其固有地具有与Mg原子低的表面和吸附能，不仅促进了平滑成核和致密沉积，还显著减轻了Mg阳极上的副反应。此外，表面的纳米片阵列均匀分布电场和Mg离子通量，增强了Mg离子转移动力学。结果，制备的（002）-Mg电极表现出前所未有的长循环性能，在3 mA cm的电流密度下，对于3 mAh cm的容量，持续超过6000 h（>8个月）。此外，配备各种电解质和阴极的相应软包电池表现出显著的容量和循环稳定性，突出了（002）-Mg电极优异的电化学兼容性。这项研究通过改变Mg的晶体结构和形态，为耐用MMBs的发展提供了新的见解。
