Electron Donation Effect of α‐Boron Nanosheet Enables Highly Stable Zinc Metal Anode

Abstract Efficiently inhibiting dendrite growth and water‐induced side reactions on Zn metal anode still remains a great challenge for the practical application of aqueous Zn ion batteries (AZIBs). Herein, an α‐boron nanosheet‐coated Zn foil (α‐B@Zn) is presented, aiming at enhancing the performance and stability of Zn metal anodes. The α‐B nanosheets are successfully synthesized via ultrasonic treatment, exhibiting a unique 2D morphology. Thanks to their hydrophobic and insulating properties, the α‐B coating significantly mitigates the hydrogen evolution reaction (HER) and surface corrosion. Furthermore, theoretical calculations and experimental results reveal that the α‐B layer facilitates the electron donation effect and endows strong chemical affinity to Zn atoms and Zn(002) plane, resulting in fast Zn desolvation kinetics and uniform Zn deposition. Consequently, the α‐B@Zn electrodes maintain satisfactory cycling performance over 2200 h with a high Coulombic efficiency of 99.7%. The assembled α‐B@Zn full cell also enables stable discharge capacity up to 4000 cycles with a capacity retention of 95.5%. The findings underscore the efficacy of the α‐B protective layer in achieving high‐performance zinc anodes for next‐generation energy storage systems.