A two-dimensional porphyrin coordination supramolecular network cathode for high-performance aqueous dual-ion battery

Iodine has great potential in the energy storage, but high solubility of I${}_3$${}^{-}$ has seriously delayed its promotion. Benefited from abundant active sites and the open channel, two-dimensional coordination supramolecular networks (2D CSNs) is considered to be a candidate for the energy storage. Herein, a 2D porphyrin-CSN cathode named Zn-TCPP for aqueous iodine dual-ion battery (DIB) shows an excellent specific capacity of 278 mAh g${}^{-1}$, and a high energy density of 340 Wh kg${}^{-1}$ at 5 A g${}^{-1}$, as well as a durable cycle performance of 5000 cycles and a high Coulombic efficiency of 98 %. Molecular orbital theory, UV/VIS, Raman spectroscopy and density functional theory (DFT) calculations reveal charge-transfer interaction between the donor of porphyrin nitrogen and the acceptor of I${}_3$${}^{-}$, and computational fluid dynamics (CFD) simulations demonstrate the contribution of 2D layered network structure of Zn-TCPP to the penetration of I${}_3$${}^{-}$. (© 2023 Wiley‐VCH GmbH)