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

Abstract

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 Zn 2+ 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 Zn 2+ -anion interactions, which slows Zn 2+ desolvation and reduces transport efficiency. To resolve these trade-offs, we have introduced tris(pentafluorophenyl)borane (TPFPB) as a multifunctional additive of Lewis acidic 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 anions via B-O/F bonds. This unique structure (i) promotes direct anion decomposition to form a robust ZnS/ZnF 2 -rich SEI; (ii) restricts anion mobility; and (iii) weakens the Zn 2+ -anion association, thereby enhancing the interfacial stability and Zn 2+ transport kinetics. As a result, Zn anodes achieve a Coulombic efficiency of 99.7% over 2800 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.