In situ Composite of Cationic Porous Organic Polymers and ɛ‐MnO ₂ as Cathode Materials for Aqueous Zinc Ion Batterys

Abstract Manganese‐based oxides are promising cathode materials for aqueous zinc ion batteries (AZIBs) due to their high energy density and low cost. However, the cycling stability is severely limited by the sluggish reaction kinetics as well as the manganese dissolution. In this work, two pyridinium ionic porous organic polymers (iPOPs) composite ɛ‐MnO 2 cathode materials, CN‐POP@MnO 2 and PN‐POP@MnO 2 , are prepared by an in situ composite method. The stable skeleton of iPOPs effectively prevents the structural collapse of the cathode. Its ionic sites and rigid network framework work together to disrupt the coordination environment of hydrated zinc ions, accelerating reaction kinetics and reducing cathode polarization. Therefore, the resultant batteries based on CN‐POP@MnO 2 and PN‐POP@MnO 2 cathodes exhibit excellent electrochemical performance. Especially for PN‐POP‐based batteries, the specific capacity is maintained at ≈96 mAh g −1 after 1500 cycles at 1 C, and the capacity attenuation rate is 0.017% per cycle.