Three-Dimensional Superlithiophilic Interphase for Dendrite-Free Lithium Metal Anodes.

Lithium metal is among the most promising anode candidates of high-energy-density batteries. However, the formed dendrites result in low Coulombic efficiency and serious security issues. Designing lithiophilic sites is one of the effective strategies to control Li deposition. Herein, we propose a three-dimensional lithiophilic N-rich carbon nanofiber with the decoration of ZnO granules as a protective layer for a dendrite-free lithium metal anode. Theoretical evaluation indicates the synergistic effects of lithiophilic ZnO and N-containing functional groups enhance lithium adsorption and trigger uniform deposition. With the lithiophilic interlayer, the lithium deposition overpotential is only ∼20, 50, and 74 mV at 1, 3, and 6 mA cm-2, respectively, which are much lower than those without the functional interlayer (∼55, 130, and 238 mV). The average Coulombic efficiency of lithium stripping and plating is up to ∼97.4% (94.0% for that without the interlayer) at 0.5 mA cm-2. Meanwhile, the Li|LiFePO4 full cell with the superlithiophilic interlayer demonstrates a high capacity retention rate of 99.6% (91.0% for that without the interlayer) over 200 cycles at 1 C. The introduction of the lithiophilic interphase could provide a convenient strategy and guidance to design the configuration for the practical application of Li metal batteries.