Structural Strategies for Germanium‐Based Anode Materials to Enhance Lithium Storage

Abstract

Recently, germanium (Ge) has been arousing increasing interest as an anode for lithium‐ion batteries (LIBs) and other energy storage devices due to its high theoretical capacity (1600 mAh g−1) and low operating voltage. There are still some critical problems to be solved before Ge can meet the high requirements for practical applications. In this Review, a series of attempts on rational design and synthesis of Ge‐based anode materials during the past few years are summarized. Structural and composition strategies that could resolve the issue of vast volume changes in Ge during cycling and enhance their electrochemical properties are focused on. The main strategies include designing nanostructures and forming Ge‐based composites and Ge‐based alloys. Lastly, the challenges for practical implementation of Ge anodes within the context of current LIB systems are discussed.

Recent progress on alloy-based anode materials for potassium-ion batteries

“…In this process, the compound first decomposes, the Ge reacts with K to form KGe and the active material reacts with K to form a compound. When the Ge-based compounds are 2D materials, such as GeSe, the reaction can be considered as GeSe + xK + + xe -↔ K x GeSe based on calculations [108,109] .…”

Ball-Milling-Assisted Grinding of GeSe2/C Hybrid Anodes for Lithium-Ion Batteries with Enhanced Electrochemical Performance

“…Meanwhile, the Li-ion diffusion coefficient of Ge (6.51 × 10 –12 cm 2 s –1 ) is 400 times than that of Si (1.41 × 10 –14 cm 2 s –1 ) at room temperature. Most importantly, Ge has isotropic lithiation behavior, which produces high reversible capacity while reducing structural damage of Ge-based anode materials. − Moreover, metal sulfide/selenide rechargeable batteries have gradually been investigated in recent years because of their large layer spacing and high gravimetric/volumetric energy densities as a result of multi-electron conversion reactions. , As reported, Herbert and Ulam first explored the use of elemental sulfur (S 8 ) in rechargeable batteries in 1962 and reached a high capacity of ∼1675 mAh g –1 . Furthermore, metal selenium materials exhibit a relatively high theoretical capacity of ∼675 mA h g –1 , although its theoretical capacity is lower than that of metal sulfur as a result of the higher mass of selenium.…”

Enhancing the electrochemical performance of a micron-sized Ge anode through in situ surface composite flower-like Zn2GeO4 for Li-ion batteries

“…Consequently, some research works have focused on designing Ge nanomorphologies (0D, 1D, 2D, and 3D) for better accommodation of the volume change and fast ion diffusion. [11][12][13] However, the expensive price of Ge and complicated nanofabrication technology present obstacles in Ge anode industrial applications.…”