Interface engineering of Zn meal anodes using electrochemically inert Al₂O₃ protective nanocoatings

Aqueous rechargeable Zn-ion batteries are regarded as a promising alternative to lithium-ion batteries owing to their high energy density, low cost, and high safety. However, their commercialization is severely restricted by the Zn dendrite formation and side reactions. Herein, we propose that these issues can be minimized by modifying the interfacial properties through introducing electrochemically inert Al₂O₃ nanocoatings on Zn meal anodes (Al₂O₃@Zn). The Al₂O₃ nanocoatings can effectively suppress both the dendrite growth and side reactions. As a result, the Al₂O₃@Zn symmetric cells show excellent electrochemical performance with a long lifespan of more than 4,000 h at 1 mA·cm⁻² and 1 mAh·cm⁻². Meanwhile, the assembled Al₂O₃@Zn//V₂O₅ full cells can deliver a high capacity (236.2 mAh·g⁻¹) and long lifespan with a capacity retention of 76.11% after 1,000 cycles at 4 A·g⁻¹.