Porous Aromatic Frameworks Enabling Polyiodide Confinement toward High Capacity and Long Lifespan Zinc–Iodine Batteries

Aqueous zinc-iodine batteries (AZIBs) are attracting increasing attention because of their high safety and abundance of resources. However, the performance of AZIBs is compromised by inadequate confinement of soluble polyiodides, the undesired shuttle effect, and slow reaction kinetics. In this study, a porous aromatic framework (PAF) with abundant benzene motifs and a well-organized pore structure is adopted as the iodine host, which exhibits high iodine adsorption capacity and robust polyiodide confinement. Both experimental characterizations and theoretical simulations indicate that the interactions between iodine species and the PAF-1 facilitate the redox reaction by coupling the electronic structures of the active species in the framework. A comparison of PAF-1, PAF-5, and PAF-11 also emphasizes the structural advantages of the high surface area and interconnected three-dimensional channels of PAF-1. Consequently, the I