Germanium holds great potential as an anode material for lithium ion batteries due to its high specific capacity and its favorable properties such as good lithium ion diffusivity and electronic conductivity. However, the high cost of germanium and large volume changes during cycling, which lead to a rapid capacity fading for bulk Ge materials, demand for nanostructured thin film devices. Herein we report the preparation and electrochemical properties of thin films of porous, inverse opal structured Ge anodes obtained via a simple, up-scalable wet-chemical route utilizing [Ge₉]⁴⁻ Zintl ions. In the absence of conductive additives, they show high initial capacities of >1300 mA h g⁻¹ and promisingly high coulombic efficiencies of up to 99.3% and deliver over 73% of their initial capacity after 100 cycles when cycled vs. metallic lithium. In contrast to many other porous structured Ge electrodes, they show very little to almost no capacity fading after an initial drop, which makes them promising candidates for long life applications.

中文翻译：

---

具有高容量保持力的锂离子电池大孔反蛋白石锗阳极的湿化学路线

锗因其高的比容量和良好的性能（如良好的锂离子扩散性和电子传导性）而具有作为锂离子电池负极材料的巨大潜力。然而，锗的高成本和循环过程中的大量体积变化，导致块状Ge材料的容量快速下降，以及对纳米结构薄膜器件的需求。本文中，我们报告了多孔多孔，反蛋白石结构的Ge阳极薄膜的制备和电化学性能，该阳极通过使用[Ge ₉ ] ^4- Zintl离子的简单，可放大的湿化学方法获得。在没有导电添加剂的情况下，它们显示出大于1300 mA hg ^-1的高初始容量与金属锂相比，经过100次循环后，库仑效率有望达到99.3％，并达到初始容量的73％以上。与许多其他多孔结构的Ge电极相比，它们在初始下降后几乎没有或几乎没有容量衰减，这使其成为长寿命应用的有希望的候选者。