Cellulose Tissue Separator With Aramid‐BaTiO ₃ Composite Dielectric Coating Proactively Stabilizing Zinc Metal Anodes

ABSTRACT

A fatal issue of zinc‐based electrochemical energy storage (ZEES) is uneven Zn ²⁺ deposition and rampant dendrite growth on the zinc metal anode, which significantly reduces the lifespan and reliability of ZEES devices. This work reports a cellulose tissue (CT) based separator with a self‐adhesive and nanoporous dielectric coating of aramid nanofibers (ANF) and barium titanate nanoparticles (BTO) to proactively stabilize zinc metal anodes. In this separator (CT‐ANF‐BTO), the ANF and BTO combine to realize high zincophilicity and pore refinement, while the BTO provides ferroelectric polarization. The benefits of CT‐ANF‐BTO, as revealed by both experimental results and theoretical calculations, synergistically provide fast/flux‐homogenized Zn ²⁺ transport, uniform electric field distribution, and low‐barrier nucleation, resulting in uniform Zn ²⁺ deposition and dendrite‐free zinc anodes. Investigation demonstrates that zinc anodes coupled with the CT‐ANF‐BTO present superior electrochemical stability, whose operation lifetime exceeds 3900, 2400, and 2000 h at 0.5, 1.0, and 2.0 mA cm ⁻² , respectively. The reliability of the CT‐ANF‐BTO in both zinc‐ion batteries and zinc‐ion hybrid supercapacitors is also validated. This work offers a high‐performing yet commercially viable cellulose‐based separator, which holds significant potential in proactively stabilizing zinc metal anodes for durable and reliable ZEES devices.