A Practical Zinc Metal Anode Coating Strategy Utilizing Bulk h‐BN and Improved Hydrogen Redox Kinetics

Achieving high‐performance aqueous zinc‐ion batteries requires addressing the challenges associated with the stability of zinc metal anodes, particularly the formation of inhomogeneous zinc dendrites during cycling and unstable surface electrochemistry. This study introduces a practical method for scattering untreated bulk hexagonal boron nitride (h‐BN) particles onto the zinc anode surface. During cycling, stabilized zinc fills the interstices of scattered h‐BN, resulting in a more favorable (002) orientation. Consequently, zinc dendrite formation is effectively suppressed, leading to improved electrochemical stability. The zinc with scattered h‐BN in a symmetric cell configuration maintains stability 10 times longer than the bare zinc symmetric cell, lasting 500 hours. Furthermore, in a full cell configuration with α‐MnO₂ cathode, increased H⁺ ion activity can effectively alter the major redox kinetics of cycling due to the presence of scattered h‐BN on the zinc anode. This shift in H⁺ ion activity lowers the overall redox potential, resulting in a discharge capacity retention of 96.1% for 300 cycles at a charge/discharge rate of 0.5 A g⁻¹. This study highlights the crucial role of surface modification, and the innovative use of bulk h‐BN provides a practical and effective solution for improving the performance and stability.