Lithiophilic anchor points enabling endogenous symbiotic Li3N interface for homogeneous and stable lithium electrodeposition

The safety hazards and short lifecycles caused by uncontrollable dendrite growth and infinite volume expansion hamper the widespread deployment of Li metal anodes. To address these issues, it is critical to regulate the nucleation and electrodeposition behaviors of Li. Herein, tetraaminophthalocyanine (TAPC) as lithiophilic anchor points modified on three-dimensional (3D) carbon skeleton (denoted as TAPC@CF) as both current collector and host material, is rationally designed for stabilizing Li metal anodes. Li3N spontaneously generated from the reaction between TAPC and Li enables upgraded electrochemical kinetics. Moreover, density functional theory (DFT) results reveal that the evenly distributed TAPC nanoparticles can effectively guide the homogeneous smooth deposition of metallic Li via strong affinity between Li and conjugation groups. Symmetrical cells containing TAPC@CF-Li anodes afford a stable cycling for 3500 h at 10 mA cm−2. Further, coupled with a high-loading LiFePO4 cathode (15.0 mg cm−2), the stability and feasibility of the modified electrode in practical cells are proved. Tetraaminophthalocyanine as lithiophilic anchor points enabling endogenous symbiotic Li3N interface is developed to redirect the Li electrodeposition for Li-metal batteries. With this composite anode of lithiophilic and Li ionic conductivity, the nucleation and electrodeposition behaviors of Li is significantly improved, enabling excellent cycling performance and high rate capability in both symmetric cells and full cells. [Display omitted] •We for the first time proposed tetraaminophthalocyanine (TAPC) as lithiophilic anchor points.•Lithiophilic TAPC modified on three-dimensional carbon skeleton is rationally designed for stabilizing Li metal anodes.•A favorable Li+ conductor and electron-insulating interface of Li3N is in situ formed.•TAPC@CF-Li anode can suppress dendrite growth effectively and exhibits promising electrochemical performance.•The full cells exhibit an excellent capacity and coulombic efficiency retention with a high mass loading of 15 mg cm−2.