Sustainable Phytic Acid-Zinc Anticorrosion Interface for Highly Reversible Zinc Metal Anodes

Although aqueous zinc-ion batteries (AZIBs) promise high capacity, low cost, and environmental friendliness, the Zn metal anode suffers from limited reversibility and unsatisfied lifespan arising from severe dendritic growth and inevitable interfacial corrosion. In this regard, constructing the artificial protective interfacial layer on the Zn metal foil has been recognized as an effective strategy to realize durable AZIBs. Inspired by the phytic acid (PA) anticorrosion conversion coating layer for industrial metal protection, herein, we designed a dense and conformal PA-Zn complex layer on the Zn anodes through a feasible, rapid wet-chemistry chelating reaction. The in situ formed uniform PA-Zn coating layer on the surface of Zn anodes can serve as a protective layer inhibiting corrosion reaction. More importantly, the desolvation energy of Zn²⁺ is effectively reduced by the PA-Zn layer, which gives rise to enhanced kinetics of Zn plating/stripping for uniform Zn deposition. Consequently, the PA-Zn metal anode delivered a low overpotential of 36 mV and a long lifespan over 1400 h at 2 mA cm^-2 with a capacity of 1 mA h cm^-2. The feasibility of PA-Zn anodes is also verified in the as-constructed PANI@V₂O₅||Zn full cells. This work paves the way for designing a multifunctional interface layer on Zn metal and promotes the development of high-performance AZIBs.