Hydrogen-Bonded Organic Framework with Desolventization and Lithium-Rich Sites for High-Performance Lithium Metal Anodes

Abstract

Effectively managing Li+ migration behaviors and addressing the issues of side reactions at the electrolyte–electrode interface is crucial for advancing high-performance lithium metal batteries (LMBs). Herein, this work introduces a two-dimensional hydrogen-bonded organic framework (HOF) enriched with multi-site H-bonding and lithiophilic sites for the first time to tailor the electronic structure and solvation chemistry in lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) based electrolyte and stabilize the lithium metal anodes (LMAs) interface. Initially, the abundant lithiophilic sites (C=O, C=N) in the HOF coordinate with Li+, acting as key electron donors to optimize the electronic structure while also reducing the desolvation energy barrier when Li+ dissociates from the solvent sheath. Moreover, the multifunctional hydrogen bonding not only acts as the “appended manipulator” to anchor -NH2 to LiTFSI and reduces the adverse reactions at the LMAs interface but also mitigates the mechanical stress during lithium deposition. As evidenced by various in/ex situ characterizations, the HOF-modified lithium-metal symmetric batteries exhibit ultra-long cycling performance (11000 h) and low voltage fluctuations at 3 mA cm-2. This unique strategy of hydrogen-bonded synergistic lithiophilic sites provides a new perspective on the design of artificial interfacial layers for stabilizing lithium metal batteries.