Heterogeneity-Segment Charge-Induced-Coupling Catalysis of Component-Selective-Type Covalent Organic Frameworks Interface toward Stabilizing Lithium Metal Anode.

Abstract

Serialized lithium traveling on the solid electrolyte interphase (SEI) of the metal anode plays a dominant role in high-energy-density lithium metal batteries. Unsatisfactorily, irregular native SEI suffers from the Li⁺ local deposition and possesses low inorganic component content, which exacerbates the growth of lithium dendrites and leads to poor battery performance. Purposefully, we fabricated the porphyrin-based covalent organic frameworks (COF-366 and COF-367) as lithium metal anode interfaces. Concretely, heterogenetic segments within COFs nodes allocate electron situations to induce component-selective catalysis, of which electron-rich nitrogen atom sites urge the N-S cleavage of bis(trifluoromethylsulfonyl)azanide (TFSI^-) and C-C breakage of 1,2-dimethoxyethane (DME), while electron-deficient benzene sites facilitate the C-O cleavage of 1,3-dioxolane (DOL), constructing a rich Li₂O/LiF-rich modification of COFs interface. The well-constructed interface facilitates rapid Li⁺ migration, distributes charge evenly, and further increases the Li⁺ flux, which achieves uniform Li⁺ deposition and suppresses dendrite growth. Consequently, the COF-366@Li anode displayed outstanding capacity stability at a high current density of 5C after 400 cycles with a capacity of 53.37 mAh g^-1 (70.99%). The COF-366@Li||LFP pouch cell further validated its practical application with an impressive capacity of 120.37 mAh g^-1 and an excellent capacity retention of 92.42% after 43 cycles with a high cathode loading of 295.2 mg. This study demonstrates the feasibility of heterogeneity-segment of customized-type COFs to induce component-selective charge-coupling catalysis toward electrolytes and manipulate SEI inorganic components for stabilizing lithium metal anode.