Anion-tethered interface engineering enabling dendrite-free lithium metal anodes

Abstract

A functionalized fiber separator with an anion-sieving effect facilitates rapid Li⁺ transfer and guides ordered Li deposition. The in situ integration of metal organic frameworks (MOFs) with polyacrylonitrile (PAN) fibers effectively prevents MOF agglomeration, and reduces the high reactivity of –CN groups with Li anodes. Real-time visualization technology confirms uniform Li deposition behavior. The Li‖Li symmetric cell demonstrates exceptional plating-stripping reversibility at 10 mA cm⁻². The Li‖LiNi_0.8Co_0.1Mn_0.1O₂ cell exhibits 17% higher capacity retention after 250 cycles than commercial polyolefin separator. This in situ chemical modification enables dendrite-free Li metal batteries through separator engineering.