Dual Breaking of Electron Cloud and Space Structure Symmetry Induced Microscopic Split-phase Interface for High-rate...

Weak dipole interactions between highly symmetric H₂O molecules and SO₄ ^2- species are the root cause of unstable electric double layer (EDL), which triggers the hydrogen evolution reaction and Zn dendrite formation, significantly impeding the commercialization of aqueous zinc-ion batteries. Herein, we designed a microscopic split-phase interface (MSPI) by dual breaking of electron cloud and space structure symmetry to suppress interfacial side reactions and achieve uniform Zn deposition. The structurally asymmetric methylurea (MU) molecules possess both hydrophobic methyl and hydrophilic amino groups, which disrupt the continuity of H-bonding network and the aggregation state of H₂O molecules, resulting in peculiar nanoscale core-shell-like clusters. Such a unique structure further evolves into MSPI at the electrode-electrolyte interface, ensuring a continuously stable EDL. The DRT analysis and MD simulation confirmed that MSPI structure is composed of the outer H₂O layer and the inner MU layer, which greatly suppress the activity of H₂O molecules and accelerate Zn²⁺ migration. Consequently, the formulated electrolyte exhibited remarkable cycle reversibility over 1500 h at a high current density of 20 mA⋅cm^-2, achieving a record-high cumulative capacity of 30 Ah⋅cm^-2. Additionally, its feasibility was demonstrated by coupling with the I₂@AC cathode, achieving an impressive 28,000 cycles at 10 A⋅g^-1.