Sb-terminated functionalized interlayer with dual-function mechanism enables highly stable lithium metal batteries

Lithium metal batteries (LMBs) have attracted huge attention due to super-high capacity and low reduction potential of lithium anode constructing high-energy/power density. However, the practical application of LMBs is significantly constrained by lithium dendrite growth and high reactivity of lithium anode. Herein, a novel functionalized interlayer that SbF 3 is tandem on HKUST-1 skeleton forming favorable Sb-terminated groups structure (HKSF@PE) were proposed and fabricated to construct highly stable LMBs. Theoretical calculations demonstrate that the Sb-terminated groups structure in this configuration display strong interaction with lithium, which can act as a cation receptor and adsorption sites, thereby promoting lithium-ion desolvation and improving lithium-ion transport kinetics. Meanwhile, in-situ XRD, Raman and DRT analyses indicate that the HKSF assist the formation of LiF-rich and lithiophilic Li 3 Sb alloys at SEI/Li interface, regulating lithium deposition morphology and reconstructing a reinforced SEI interlayer. Consequently, Li|HKSF@PE|Li symmetric cell exhibits exceptional stability over 2500 hours at 2 mA cm -2 with 1 mAh cm -2 , and Li|HKSF@PE|LFP full cell demonstrates a high-capacity retention of 92.0% after 220 cycles even at a high rate of 5C. This work reveals the important role of terminated groups to achieve homogeneous lithium deposition and provide a way to construct stable LMBs. Sb-terminated lithiophilic interlayer of HKUST-1 tandem SbF 3 (HKSF) with dual-function mechanism of regulate lithium-ions behavior and reconstruct a stable SEI is applied to inhibit Li dendrites growth and alleviate side reaction for high LMBs. Benefiting from the unique terminated group structure and dual-function regulatory mechanism, Li|HKSF@PE|Li symmetric cell delivers impressive stability over 2500 h at 2 mA cm -2 with 1 mAh cm -2 , Li|HKSF@PE|Cu cell exhibits the average CE of 97.5% even after 560 cycles at 0.5 mA/cm 2 with 0.5 mAh/cm 2 , and Li|HKSF@PE|LFP full cell displays a decay rate of 0.038% per cycle after 260 cycles even at high rate of 2C. • The lithiophilic interlayer of HKUST-1 tandem SbF 3 with Sb-terminated groups structure is applied to regulate Li-ion behavior and reconstruct SEI interface. • The Sb-terminal groups structure as cation receptor promotes Li + clusters desolvation and improve transport kinetics. • The multi-step in-situ reaction form the stable SEI/Li anode interface with uniformly distributed LiF and Li 3 Sb alloys, which regulate the Li + deposition morphology and reconstruct a reinforced SEI. • The reversible and stable performance of lithium metal battery is significantly improved.