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.