Kinetic Regulation of Zn(002) Textured Interfaces for Highly Reversible Zn–Iodine Batteries

Abstract

The commercialization of zinc-ion batteries is severely hindered by anode instability, as hydrogen evolution reactions and Zn dendrite growth lead to low Coulombic efficiency and short cycle life. Here, we propose a kinetic regulation strategy of spatial electrostatic field layer (EFL), based on the conjugated system of tetrasulfonated cobalt phthalocyanine (CoPcS₄), to enhance the preferred Zn(002)-oriented deposition. Experimental characterizations and theoretical calculations confirm that CoPcS₄ can preferentially adsorb on the electrode surface and form a stable solid electrolyte interface, which prevents zinc anode from the direct contact with aqueous electrolyte. The conjugated planar structure of CoPcS₄ further generates a delocalized EFL, which promotes Zn²⁺ desolvation, accelerates ion transport, and ensures uniform electric field distribution. Moreover, it can effectively promote the preferred Zn(002) deposition and maintains a dense, smooth anode surface during cycling. This strategy achieves excellent cycling stability of 3500 cycles in Zn//Zn symmetry cells under extreme condition of 50 mA cm⁻². In a Zn//I₂ battery, it demonstrates exceptional stability even at an ultra-high current density of 50 C, highlighting its great potential in massive energy storage.