Construction of carboxylated aramid nanofiber protective layer for stable zinc anodes

Zinc-ion batteries (ZIBs) are promising candidates for safe and environmentally benign energy storage systems because they possess a high theoretical capacity (820 mAh g −1 ), abundant natural reserves, a low electrochemical potential (−0.76 V vs. SHE), and superior safety characteristics. However, the practical application of zinc (Zn) anodes is hindered by undesirable reactions, including Zn dendrite growth, hydrogen evolution, and Zn anode corrosion. In this study, we designed a novel Zn anode protective layer through carboxylation modification of aramid nanofibers (ANFs). This engineered protective layer aims to regulate Zn deposition behavior and enhance battery cycling stability. Specifically, the carboxylated ANF (cANF) layer enhances hydrophilicity, improving electrolyte wettability at the anode-electrolyte interface. Furthermore, it effectively modulates the Zn 2+ deposition orientation, suppressing dendritic growth. Consequently, the cANF@Zn symmetric cell demonstrated stable cycling for 750 h at 3 mA cm −2 and 1 mAh cm −2 , significantly outperforming the performance of the cells with bare Zn anode. Moreover, the cANF@Zn | V 2 O 5 full cell exhibited substantially enhanced cycling stability compared to the cells using bare Zn anodes. These results demonstrate that the introduction of cANF layer is an effective strategy for mitigating critical challenges of Zn anodes.