Zinc-affinitive heteroatom-incorporated artificial interfacial layer for high-performance aqueous zinc metal batteries

The inherent safety, affordability, and environmental friendliness of aqueous zinc metal batteries (AZMBs) have garnered considerable attention, positioning them as promising candidates for next-generation energy storage systems. However, the practical deployment of AZMBs is hindered by interfacial challenges, such as uncontrolled dendrite growth, hydrogen evolution reaction (HER), and corrosion between anodes and aqueous electrolytes (AEs). Solving these issues requires a well-engineered artificial layer that can regulate Zn²⁺ transport and suppress side reactions. In this study, we propose a synergistic strategy to incorporate electronegative heteroatoms for a zinc-affinitive nitrogen and sulfur co-incorporated TiO₂ (N,S − TiO₂) artificial interfacial layer. This approach effectively breaks the symmetry of TiO₂ and modulates its surface structure, leading to the presence of abundant zincophilic polar sites, which are capable of simultaneously lowering interfacial migration barriers and enhancing the compatibility with polymer chains. The incorporation of N,S − TiO₂ into the polymer matrix as an artificial interfacial layer effectively suppresses HER and corrosion reactions, while constructing a continuous, efficient interfacial Zn²⁺ conduction pathway. In consequence, the symmetric cells with N,S − TiO₂ achieve a remarkably extended cycle life of 8000 h at 1 mA cm⁻², and more than 2000 h even at high current densities of 5 mA cm⁻². Furthermore, a Zn||MnO₂ full cell exhibits impressive capacity retention of 81.83 % over 500 cycles at 1 A g⁻¹. These results demonstrate the promising potential of the N,S − TiO₂ interfacial layer to enable stable and efficient AZMB operation.