In-situ construction of lithophilic Li3Sb layer on nickel foam to induce low nucleation barrier and uniform deposition for stable lithium-metal anode

Uncontrollable dendrite growth and safety issues of lithium-metal anode (LMA) greatly limited its commercial development. Therefore, designing uniform lithophilic layers on three-dimensional (3D) host structures is interesting yet challenging for inducing homogeneous Li⁺ flux and deposition. Herein, we propose an in-situ construction of dense lithiophilic Li₃Sb layer on nickel foam (Li₃Sb@NF) as a 3D host of LMA to inhibit the growth of dendrites. The results show that Li₃Sb produced by alloying reaction owns good lithophilic affinity, which provides abundant nucleation sites for homogeneous lithium deposition. Meanwhile, the 3D structure effectively reduces the local current density and inhibits the growth of dendrites, which are confirmed by kinetic analysis and in-situ optical observation of Li plating/stripping behaviors. Besides, the density functional theory (DFT) calculation verifies that Li₃Sb layer owns a high Li⁺ adsorption energy and effectively reduces the nucleation energy barrier of Li metal. Consequently, the Li₃Sb@NF electrode delivers an enhanced average Coulombic efficiency (CE) of 99.65 % for 200 cycles at 2 mA cm^-2 with 2 mAh cm^-2. The Li-Li₃Sb@NF symmetrical cells both exhibit high reversibility at 1 mA cm^-2 with 1 mAh cm^-2 (>3800 h) and 5 mA cm^-2 (>1800 h). Moreover, Li-Li₃Sb@NF//LiFePO₄ full cell also acquires superior long-term cycling with 500 cycles at 1C (78.8 % retention). This work provides a simple, effective strategy for the protection of lithium metal anode via in-situ construction of a lithophilic alloy layer.