Interfacial Regulation with 2D MoN Nanosheets Enables Dendrite-Free Lithium Metal Anodes

Abstract

The practical application of lithium metal anodes under high-areal-capacity conditions is hindered by uncontrollable lithium dendrite growth and significant volume changes. This work presents a facile dispersion-folding-mechanical rolling method to fabricate a lamellar structured Li/MoN composite electrode by incorporating lithiophilic two-dimensional (2D) molybdenum nitride (MoN) nanosheets into lithium metal. Density functional theory (DFT) calculations reveal that the MoN(002) and MoN(200) crystal planes exhibit strong lithium adsorption energies and lower diffusion energy barriers for lithium atoms, significantly enhancing the lithium diffusion kinetics within the electrode bulk. The MoN-induced inorganic-rich solid electrolyte interphase (SEI), comprising LiF, Li 3 N, and Li 2 O, enhances interfacial ionic conductivity and mechanical strength (Young's modulus ≈ 7.86 GPa after cycling), collectively suppressing dendrite growth. Furthermore, lithium metal preferentially deposits into the interlayer gaps between the MoN nanosheets during plating, effectively accommodating the substantial volume fluctuations during cycling. Consequently, the Li/MoN symmetric cells achieve exceptional cyclability exceeding 540 h at 1 mA cm - 2 and 3 mAh cm -2 , 680 h at 1 mA cm -2 and 1 mAh cm -2 . When coupled with a highloading LiNi 0.83 Co 0.11 Mn 0.06 O 2 (NCM83) cathode, the Li/MoN||NCM83 full cell maintains 75% capacity after 200 cycles at 2 C. Moreover, a 1 Ah Li/MoN||NCM83 pouch cell demonstrates an exceptional capacity retention of 98.9% after 80 cycles, underscoring its practicality for high-energy-density batteries.