RESUMO
Aqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti-freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a "nucleation-merge-growth" process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600â cycles and in Zn/Zn symmetric cells for over 3000â hours at 1.0â mA cm-2. Furthermore, Na0.33V2O5/Zn and α-MnO2/Zn full cells display promising capacity and sustained stability over 500â cycles at room and sub-zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite-free zinc metal batteries.