Artificial aluminum-doped SiO2 aerogel coating layer regulating zinc ions flow for highly reversible dendrite-free zinc anodes

As a sustainable, safe, and cost-effective alternative to conventional lithium-ion batteries, aqueous rechargeable zinc-metal-based batteries have attracted significant attention in large-scale energy storage. However, their practical application is hindered by zinc anode degradation, primarily dendrite growth and corrosion, which compromise battery performance and lifespan. Herein, we present an aluminum-doped silica (Al-SiO2) aerogel coating layer to address these issues. The aluminum-doped silica aerogel coating layer offers improved hydrophilicity and zinc ion adsorption capabilities because of its porous structure, high surface area, and functional groups. By facilitating uniform zinc ion deposition and providing a physical barrier against corrosion, the Al-SiO2 aerogel coating layer significantly mitigates dendrite formation and extends the electrochemical stability and operational lifespan of aqueous rechargeable zinc-metal-based batteries. Symmetric cell tests reveal that zinc anodes coated with Al-SiO2 can achieve stable cycling over 3000 h, indicating exceptional reversibility and rate performance, much better than that of the bare Zn anode. Furthermore, the Al-SiO2 aerogel-coated zinc anode coupled with MnO2 cathode forms a stable rechargeable full battery. This work contributes to the body of knowledge on advanced materials for energy storage, highlighting the potential of aerogel coatings as a scalable and effective solution for improving the performance and durability of zinc metal anode for aqueous rechargeable zinc-metal-based batteries.