Lewis acidic molecule-modulated synchronous anion immobilization and decomposition towards a robust solid electrolyte interphase with enhanced Zn²⁺ kinetics

Zn metal anodes in aqueous zinc-ion batteries (AZIBs) face significant challenges for practical applications, due to detrimental dendrite growth and severe side reactions arising from unstable solid electrolyte interface (SEI) layers, sluggish Zn²⁺ transport kinetics, and irreversible Zn deposition. While anion regulation is a promising strategy for constructing a stable SEI layer, typical approaches mainly rely on strengthening Zn²⁺–anion interactions, which slows Zn²⁺ desolvation and reduces transport efficiency. To resolve these trade-offs, we have introduced tris(pentafluorophenyl)borane (TPFPB) as a multifunctional Lewis acidic additive that enables synchronous anion immobilization and decomposition. Theoretical and experimental results reveal that the electron-deficient boron centers and pentafluorophenyl groups in TPFPB can effectively anchor OTf− anions via B–O/F bonds. This unique structure (i) promotes direct anion decomposition to form a robust ZnS/ZnF₂-rich SEI; (ii) restricts anion mobility; and (iii) weakens the Zn²⁺–anion association, thereby enhancing the interfacial stability and Zn²⁺ transport kinetics. As a result, the half cells achieve an average Coulombic efficiency of 99.5% over 2900 cycles, and the vanadium-based full cells deliver a lifespan exceeding 40 000 cycles. This work presents a novel anion-regulation strategy that simultaneously stabilizes the Zn interface and accelerates ion transport, offering a promising path toward high-performance AZIBs. © 2026 The Author(s). Published by the Royal Society of Chemistry