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(-).

Automated summary

Iodine has great potential in energy storage, but its high solubility of I-3(-) has hindered its promotion. Two-dimensional coordination supramolecular networks (2D CSNs) with abundant active sites and open channels are considered a candidate for energy storage. In this study, a 2D porphyrin-CSN cathode named Zn-TCPP exhibited excellent specific capacity (278 mAh g(-1)), high energy density (340 Wh kg(-1)) at 5 A g(-1)), durable cycle performance (5000 cycles), and high Coulombic efficiency (98%) in an aqueous iodine dual-ion battery (DIB). Molecular orbital theory, UV/VIS, Raman spectroscopy, and density functional theory (DFT) calculations showed charge-transfer interaction between the donor of porphyrin nitrogen and the acceptor of I-3(-), while computational fluid dynamics (CFD) simulations demonstrated the contribution of the 2D layered network structure of Zn-TCPP to the penetration of I-3(-).