Uniform lithium deposition regulated by lithiophilic Mo3N2/MoN heterojunction nanobelts interlayer for stable lithium metal batteries

Abstract

Lithium metal batteries (LMBs) are of significant importance for high-energy rechargeable batteries owing to its ultra-high theoretical specific capacity and lowest reduction potential. However, the lithium dendrite growth during the continuous plating/stripping process results in poor cycle property, serious security issues and low Coulombic efficiency to working LMBs. To effectively inhibit lithium dendrite issues, a multifunctional lithiophilic interlayer constructed by heterostructural Mo3N2/MoN nanobelt (MoNx) is exploited as regulator to adjust lithium deposition. The results reveal that MoNx/PP exhibits high lithium-ion transference number, ion conductivity and excellent electrolyte wettability, which action synergistically to regulate lithium-ion diffusion and flux. DFT calculation further demonstrates that the co-existence of heterostructure and polar bonds can effectively enhance the interaction between MoNx and lithium, which can supply more deposition sites for promoting homogenous and smooth lithium plating. The advantages mentioned above endow symmetric Li//Li cell used MoNx/PP with a super-long-life of 1500 h at 5 mA cm−2. Furthermore, Li//LiFePO4 full cell presents excellent cycling stability and ultra-low-capacity decay rate of 0.033 %/cycle after 500 cycles even at 3C. This work offers a creative strategy and insight to reasonably design lithiophilic interlayer to regulate Li uniform depositions in working LMBs.