Regulation of Interfacial Ion Transport via Honeycomb-Architected Covalent Organic Frameworks for Lithium Metal Batteries.

Abstract

This study pioneers vertically aligned honeycomb covalent organic framework (HCCOF) on graphene oxide (HCCOF-GO) through one-pot colloidal assembly, establishing a paradigm for interface-engineered 2D heterostructures in lithium metal batteries (LMBs). Mechanistically, the vertical COF alignment via interfacial π-π conjugation preserves intrinsic 1.15 nm hexagonal pores while integrating Go's electron transport capabilities. When deployed as an artificial solid-electrolyte interphase (ASEI), this architecture demonstrates triple functionalities: i) "lithiophilic" nanopores enabling dendrite-free Li⁺ flux (migration barrier 0.29 eV), ii) polarized interfaces regulating anion-solvent coordination, and iii) gradient organic-inorganic solid electrolyte interphase (SEI) formation. The modified anodes achieve record Li⁺ transference number (t_Li ⁺ = 0.96) with ultra-long cyclability (>3000 h at 10 mA cm^-2, 10 mAh cm^-2) and minimal polarization (ΔV = 13 mV). Competitive electrochemical performance across diverse battery configurations confirms practical viability: the HCCOF-GO@Li‖NCM811 full cell retains 81.1% of its initial capacity after 100 cycles at a practical loading of 4.5 mAh cm^-2. Corresponding pouch cells (368 Wh kg^-1) maintain 82.3% capacity retention after 40 cycles, while HCCOF-GO@Li‖LCO cell demonstrates remarkable cycling stability (500 cycles@80.3%) at a high voltage of 4.7 V.