Coupling High Hardness and Zn Affinity in Amorphous–Crystalline Diamond for Stable Zn Metal Anodes

The highly reversible plating/stripping of Zn is plagued by dendrite growth and side reactions on metallic Zn anodes, retarding the commercial application of aqueous Zn-ion batteries. Herein, a distinctive nano dual-phase diamond (NDPD) comprised of an amorphous–crystalline heterostructure is developed to regulate Zn deposition and mechanically block dendrite growth. The rich amorphous–crystalline heterointerfaces in the NDPD endow modified Zn anodes with enhanced Zn affinity and result in homogeneous nucleation. In addition, the unparalleled hardness of the NDPD effectively overcomes the high growth stress of dendrites and mechanically impedes their proliferation. Moreover, the hydrophobic surfaces of the NDPD facilitate the desolvation of hydrate Zn2+ and prevent water-mediated side reactions. Consequently, the Zn@NDPD presents an ultrastable lifespan exceeding 3200 h at 5 mA cm–2 and 1 mAh cm–2. The practical application potential of Zn@NDPD is further demonstrated in full cells. This work exhibits the great significance of a chemical–mechanical synergistic anode modification strategy in constructing high-performance aqueous Zn-ion batteries.