Hydrophobic Ion Barrier‐Enabled Ultradurable Zn (002) Plane Orientation towards Long‐Life Anode‐Less Zn Batteries

Abstract

Gradual disability of Zn anode and high negative/positive electrode (N/P) ratio usually depreciate calendar life and energy density of aqueous Zn batteries (AZBs). Herein, within original Zn²⁺-free hydrated electrolytes, a steric hindrance/electric field shielding-driven "hydrophobic ion barrier" is engineered towards ultradurable (002) plane-exposed Zn stripping/plating to solve this issue. Guided by theoretical simulations, hydrophobic adiponitrile (ADN) is employed as a steric hindrance agent to ally with inert electric field shielding additive (Mn²⁺) for plane adsorption priority manipulation, thereby constructing the "hydrophobic ion barrier". This design robustly suppresses the (002) plane/dendrite growth, enabling ultradurable (002) plane-exposed dendrite-free Zn stripping/plating. Even being cycled in Zn‖Zn symmetric cell over 2150 h at 0.5 mA cm^-2, the efficacy remains well-kept. Additionally, Zn‖Zn symmetric cells can be also stably cycled over 918 h at 1 mA cm^-2, verifying uncompromised Zn stripping/plating kinetics. As-assembled anode-less Zn‖VOPO₄ ⋅ 2H₂O full cells with a low N/P ratio (2 : 1) show a high energy density of 75.2 Wh kg^-1 _{full electrode} after 842 cycles at 1 A g^-1, far surpassing counterparts with thick Zn anode and low cathode loading mass, featuring excellent practicality. This study opens a new avenue by robust "hydrophobic ion barrier" design to develop long-life anode-less Zn batteries.