Gradient Interfacial Layer Design for Zinc Metal Anode: Breaking the Trade‐Off Between Zincophilicity and Zincophobicity

ABSTRACT The sluggish kinetics and poor thermodynamic stability significantly hinder the practical application of zinc (Zn) metal anodes. The artificial zincophilic interface accelerates Zn ²⁺ deposition but induces intense side reactions, whereas the zincophobic one exhibits the opposite effect. Herein, we innovatively construct a gradient zincophobic–zincophilic interface layer on the zinc anode (PDA‐PSBMA@Zn) via self‐assembly to break the above trade‐off. The aromatic rings and alkyl chains accumulating at the electrode‐facing side enhance the thermodynamic stability, while the abundant sulfonate groups near the electrolyte‐facing side accelerate Zn ²⁺ desolvation, transport, and deposition kinetics, thereby inducing uniform deposition along the (002) plane. Consequently, symmetric cells with PDA‐PSBMA@Zn demonstrate stable cycling for 4200 h at a current density of 1 mA cm ⁻² and 820 h at 20 mA cm ⁻² . Zinc‐ion hybrid capacitors assembled with PDA‐PSBMA@Zn and activated carbon retain 97.74% capacity retention after 40 000 cycles at 5 A g ⁻¹ . This work provides a feasible strategy for balancing the kinetic rate and thermodynamic stability of metal anodes in aqueous energy storage devices.