High Mass Loading of Edge-Exposed Cu₃P Nanocrystal in 3D Freestanding Matrix Regulating Lithiophilic Sites for High-Performance Lithium Metal Anode

Lithium (Li) dendrites and volume expansion during repeatedLiplating and stripping processes are the major obstacles to the developmentof advanced Li metal batteries. Li nucleation and dendrite growthcan be controlled and inhibited spatially by using 3-dimensional (3D)hosts together with efficient lithiophilic materials. To realize next-generationLi-metal batteries, it is critical to effectively regulate the surfacestructure of the lithiophilic crystals. Herein, exposed-edged Cu3P faceted nanoparticles anchored along the interlaced carbonnanofibers (ECP@CNF) are developed as a highly efficient 3D Li host.Through the 3D interlaced rigid carbon skeleton, volume expansioncan be accommodated. The (300)-dominant edged crystal facets of Cu3P with abundant exposed P3- sites not onlyexhibit strong micro-structural Li affinity but also have relativelyhigh charge transference to nucleate uniformly and effectively, resultingin reduced polarization. Consequently, under a high current densityof 10 mA cm(-2) with a high discharge of depth (60%),ECP@CNF/Li symmetric cells demonstrate outstanding cycling stabilityfor 500 h with a small voltage hysteresis of 32.8 mV. Notably, theECP@CNF/Li parallel to LiFePO4 full cell exhibits a more stablecycling performance for 650 cycles under a high rate of 1 C, withcapacity retention up to 92% (N/P = 10, 4.7 mg cm(-2) LiFePO4). Even under a limit Li (3.4 mA h) with an N/Pratio of 2 (8.9 mg cm(-2) LiFePO4), ECP@CNF/Li parallel to LiFePO4 full cell can also demonstrate excellent reversibility andstable cycling performance with higher utilization of Li. This workprovides an insight view into constructing high-performance Li-metalbatteries under more strict conditions.