Porous Organic Cage with 3D Interpenetrated Electronegative Channels as Artificial SEI for Highly Reversible Zinc Anode

Abstract Aqueous zinc batteries (AZBs), as a newly emerging candidate for large‐scale energy storage, suffer from severe dendrite growth, hydrogen evolution, and Zn‐metal corrosion, posing a huge challenge for commercial application. Herein, a representative porous organic cage (POC), namely CC3, is proposed as an artificial solid electrolyte interphase (ASEI) through a facile electrospray technique. Owing to the characteristic internal cavities, 3D interpenetrated channels, partial disorder enhanced porosity, zincophilicity, and solution processability, the CC3‐ASEI is not only conducive to enable rapid desolvation and migration of Zn 2+ through ASEI, but also affords uniform Zn 2+ flux and oriented Zn deposition, thus effectively suppressing dendrite growth and parasitic reactions. As a result, the CC3‐ASEI bestows an outstanding Coulombic efficiency of 99.86% for 5000 cycles in the Zn||Ti asymmetric cell and remarkably stable Zn plating/stripping over 7100 h in the Zn||Zn symmetric cell. Besides, the implementation of this CC3‐ASEI also markedly improves the rate capability and cycling stability of AZBs with various cathodes, highlighting the great potential of employing POCs to promote the practical application of AZBs.