Supercritical CO

Regulating Zinc (Zn) nucleation and crystal growth on the anode surface is critical for reliable aqueous Zn metal batteries. However, achieving scalable and uniform surface modifications remains challenging. A Supercritical CO2-induced surface autogenous mineralization (SAM) strategy is introduced to fabricate a large-area, uniform, and crystalline Smithsonite autogenous regulating layer (ARL) on Zn foil. SAM enables in situ generation of H2CO3 and direct reactions with Zn under supercritical conditions, suppressing Zn2+ hydrolysis and inducing in situ mineralization. The ARL well-defined facets provide zincophilic sites, promoting single-crystal Zn nucleation and facilitating dense epitaxial deposition, thereby mitigating dendrites and enhancing cycling stability. The modified electrodes achieve over 1200 h with 99.48% Coulombic efficiency in SZn-4||Cu cells, over 3500 h in symmetrical cells, and over 8000 cycles in full cells at high current densities. This scalable SAM route offers a robust platform for high-performance, long-life Zn anodes in next-generation aqueous energy storage.