Interface-engineered electrolyte–electrode design with lithium nitrate for durable aqueous zinc-ion batteries in sustainable energy applications

Aqueous zinc-ion batteries (AZIBs) are promising candidates for next-generation large-scale renewable energy storage systems owing to their intrinsic safety, cost-effectiveness, and environmental compatibility. However, their practical deployment is limited by dendritic zinc growth, hydrogen evolution, and unstable electrolyte–electrode interfaces, which reduce cycle life and operational reliability. In this work, we present an interface-engineered electrolyte–electrode composite approach utilizing lithium nitrate (LiNO₃) as a multifunctional additive to regulate Zn²⁺ solvation and promote controlled deposition. Through competitive ligand coordination, NO₃⁻ anions partially replace H₂O and SO₄²⁻ ligands in the Zn²⁺ solvation shell, enabling enhanced ionic mobility, uniform metal deposition, and suppressed ZnSO₄ aggregate formation. Optimized LiNO₃ concentration (0.075 wt.%) yields Zn||Ti half-cells with over 500 stable cycles and an average Coulombic efficiency of 99.7%, while Zn||Zn symmetric cells exhibit dendrite-free operation exceeding 1300 h even under high current densities. Complementary molecular dynamics simulations and experimental characterization reveal preferential deposition along the Zn (002) crystal plane and the formation of a robust, Li₃N-containing solid electrolyte interphase, improving interfacial conductivity and corrosion resistance. Full-cell tests with MnO₂ cathodes demonstrate an initial specific capacity of 263 mAh·g⁻¹, retaining 65% after 300 cycles at 1 A·g⁻¹, with Coulombic efficiency consistently above 99.7%. This composite interface design strategy provides a scalable pathway for engineering durable zinc-based batteries, directly supporting the development of high-performance, long-life energy storage modules for grid-level renewable integration and other engineering applications.