Enabling high-performance sodium metal anodes by 2D nanomaterials engineering: a review

Sodium metal batteries (SMBs) are an affordable and energy-dense alternative to meet future energy storage requirements. However, the commercialization of sodium metal anodes (SMAs) is facing challenges of unstable solid electrolyte interphase (SEI), uncontrolled dendrite growth, and large volume change during cycles. To overcome these obstacles, a range of strategies has been explored including the design of composite anode, artificial SEI, modification of separator, as well as solid-state electrolyte. Two-dimensional (2D) materials with atomic thickness exhibit large surface area, attractive physicochemical properties, and high mechanical strength, which offers great promise for enabling SMBs with enhanced stability, cycling performance, and safety. In this review, we first summarize the recent development of SMAs that employ 2D nanomaterials engineering. In addition, different mechanisms of 2D nanomaterials in stabilizing SMAs are discussed in detail. Last, we highlighted future opportunities for 2D nanomaterials to enable the next-generation high-performance SMBs.