Synergistic design of a three-dimensional and multifunctional fluorine-doped hollow carbon nanofiber coatings with in-situ dynamically formed ZnF2 interphase for long-term stable aqueous dendrite-free zinc anodes

While aqueous zinc-ion batteries (AZIBs) show great promise for safe energy storage, their practical implementation is impeded by performance issues at the Zn anode, such as parasitic side reactions, hydrogen evolution, and dendritic growth. Here, we report a fluorine-doped carbon nanofiber (FCNF) 3D coating that provides dynamic, durable protection for the zinc anode. The coating's 3D architecture, intrinsic negative charge, and hydrophobicity synergistically guide uniform zinc deposition while inhibiting parasitic reactions. More importantly, a ‘sustained supply and dynamic formation’ mechanism is realized, where C F bonds within the FCNF dynamically cleave during cycling to enable the continuous in-situ formation of a ZnF 2 layer that persistently suppresses side reactions. Consequently, symmetric cells employing FCNF-protected anodes demonstrate an operational lifetime exceeding 3400 h at a high areal capacity of 2.5 mAh cm −2 . Moreover, when assembled with an ammonium vanadate cathode, the full cell stably cycles for over 1000 cycles at 5 A g −1 , maintaining 82% of its initial capacity. This work introduces an approach that synergistically combines physical guidance and dynamic chemical repair, offering a robust solution for developing highly stable and safe metal batteries with aqueous electrolytes.