2D Materials for Lithium/Sodium Metal Anodes

In view of their high theoretical specific capacity and low electrochemical potential, lithium/sodium metal anodes (MAs) have been revisited in recent years in the context of high-energy-density storage systems. However, the infinite volume change and the uncontrollable dendrite growth of MAs during cycles are obstructing the development of commercialization. Numerous strategies have been explored to surmount the barriers, including composite anode preparation, separator modification, artificial solid electrolyte interphase, and solid-state electrolyte fabrication. With atomic thickness, two-dimensional (2D) materials possess ultrahigh specific surface area, abundant surface chemistry, and high mechanical strength along with facile processibility. These properties render 2D materials useful in all components of lithium/sodium metal batteries, improving their cycle stability and safety performance of the whole system. Herein, current progress of 2D materials for MAs is summarized. Their limitations are also discussed. New perspectives and future directions for this area are also provided. With numerous new 2D materials discovered or underexplored, it is expected that 2D materials will find great opportunities in high-energy-density lithium/sodium metal batteries.