A liquid-bandage-inspired conformal nitrocellulose-based interphase with ion regulation for highly stable zinc metal...

Despite the inherent safety and low cost of aqueous Zn-ion batteries (AZIBs), the practical application of Zn metal anodes is severely hindered by dendrite growth and parasitic reactions. Herein, inspired by the adhesive and conformal characteristics of liquid bandages, we report a rigid-flexible nitrocellulose/ricinoleic acid (NCRA) interphase with ion-regulating capability for highly stable Zn metal anodes through a facile blade-casting approach. Ricinoleic acid is incorporated as a plasticizer to improve the flexibility of the otherwise rigid nitrocellulose film, enabling conformal and adhesive contact of the NCRA interphase with the Zn anode. The highly zincophilic and electronegative nitro and carboxyl groups endow the NCRA interphase with multifunctional ion-regulation functions, including a lowered nucleation energy barrier, accelerated desolvation kinetics of hydrated Zn²⁺ ions, uniform Zn²⁺ flux, and repulsion of SO₄^2- anions, collectively contributing to dendrite-free Zn deposition. Meanwhile, the NCRA interphase serves as a physical barrier that effectively shields the Zn anode from bulk water, thereby suppressing water-induced side reactions. Furthermore, this conformal interphase accommodates volume fluctuations during repeated Zn plating/stripping, thereby effectively preserving interfacial integrity and long-term protection. Consequently, the NCRA@Zn anode demonstrates highly reversible and stable plating/stripping behavior for over 5000 h at 5 mA cm^-2. After 2500 cycles at 10 A g^-1, the full cell employing an NH₄V₄O₁₀ cathode preserves 86.5% of its initial capacity. This work offers a simple yet powerful interfacial strategy toward long-life, dendrite-free Zn anodes for practical AZIBs.