Functional Layer with Electron-Rich Domain and Hierarchical Ion Channel toward Stable Zinc Anode.

Abstract

Aqueous zinc batteries represent a promising solution for energy storage applications, owing to their inherent safety and cost-effectiveness. However, challenges such as corrosion, hydrogen evolution, dendrite formation, and poor reversibility remain. To address these issues, this study presents a series of 2D porphyrin polymers featuring electron-rich domains and hierarchical ion channels as a protective layer for stabilizing zinc anodes. The hierarchical ion channels, characterized by a pore size of 3.7 nm, facilitate rapid ion transport and guide uniform Zn²⁺ deposition. The active porphyrin units, with electron-rich domains, could promote rapid Zn²⁺ deposition through enhanced Zn²⁺ adsorption, while also provide anticorrosion properties through the protective layer, thereby ensuring long-term cycle stability. As a result, the NiTPP@Zn symmetrical batteries demonstrate stable cycling performance for over 1700 h at 5 mA cm^-2. Furthermore, the soft pack batteries exhibit sustained cycles with high specific capacity, highlighting the potential of NiTPP in enhancing the performance of aqueous zinc batteries for energy storage applications.