Uncovering diverse roles of zincophilic and hydrophobic interactions at composite interfaces to enhance the longevity of zinc-ion batteries

Abstract

Aqueous zinc-ion batteries (AZIBs) are pivotal for achieving net-zero goals, yet their commercialization is impeded by zinc dendrites, parasitic reactions, and interfacial instability. Current debates persist on the interplay between zincophilic-hydrophilic and zincophobic-hydrophobic interactions at the anode-electrolyte interface. Herein, a conceptual framework that decouples these competing effects was proposed, enabling the rational design of a dual-layer architecture with an inner zincophilic layer for Zn²⁺ flux homogenization and an outer hydrophobic layer for water shielding. Through in situ and ex situ analyses, the synergistic mechanism was elucidated. During the cycling process, the zincophilic interface guides uniform Zn deposition, while the hydrophobic coating suppresses H₂O-induced side reactions. This dual modification achieves a Zn||Cu cell with an unprecedented 99.89% Coulombic efficiency and 975-cycle stability. This work resolves the long-standing controversy over interfacial affinity design, offering a scalable and industrially viable strategy to enhance AZIBs’ durability without sacrificing energy density.