Reconfiguring Zn Deposition Dynamics via Epitaxial Zn2+ Pathway in Profiled Viscose Rayon for Long-Cyclability Zinc-Ion Batteries

Abstract

Rechargeable aqueous zinc-ion batteries (AZIBs) are promising candidates for stationary energy storage due to their intrinsic safety, environmental sustainability, and cost-effectiveness. However, their cycling stability is hammered by uncontrollable dendrite formation and hydrogen evolution reaction (HER) at Zn anode. Here, we propose a cost-effective commercial viscose fabric, derived from profiled viscose rayons, as a versatile separator for reconfiguring the interface dynamics of Zn deposition, enabled by the surface grooves with abundant carboxyl groups on profiled viscose rayons. Results show that carboxyl groups facilitate the desolvation of hydrated Zn2+ to suppress HER while surface grooves provide epitaxial Zn2+ pathways for rapid horizontal transport of Zn2+ on the surface of Zn anode which promotes the transition of Zn deposition manner from 2D to 3D diffusion and hence regulates the grow direction of Zn crystals from (101) to (002) to form a uniform and dense Zn deposition on anode. Consequently, AZIBs implementing the viscose fabric separator exhibit high battery performance, including improved cycle life over 4600 h at 1 mA cm-2 and enhanced rate capability. This work highlights the significant potential of profiled viscose rayon in reconfiguring the interface dynamics of Zn deposition, providing guidance for the design of advanced separators in AZIBs.