Interfacial Designing of MnO2 Half‐Wrapped by Aromatic Polymers for High‐Performance Aqueous Zinc‐Ion Batteries

Abstract

AbstractDue to the excellent specific capacity and high working voltage, manganese oxide (MnO2) has attracted considerable attention for aqueous zinc‐ion batteries (AZIBs). However, the irreversible structural collapse and sluggish ionic diffusion lead to poor rate capability and inferior lifespan. Herein, we proposed a novel organic/inorganic hybrid cathode of carbon‐based poly(4,4′‐oxybisbenzenamine)/MnO2 (denoted as C@PODA/MnO2) for AZIBs. Various in/ex situ analyses and theoretical calculations prove that PODA chains with C=N groups can provide a more active surface/interface for ion/electron mobility and zinc ion storage in the hybrid cathode. More importantly, newly formed Mn−N interfacial bonds can effectively promote ion diffusion and prevent Mn atoms dissolution, enhancing redox kinetics and structural integrity of MnO2. Accordingly, C@PODA/MnO2 cathode exhibits high capacity (321 mAh g−1 or 1.7 mAh cm−2 at 0.1 A g−1), superior rate performance (88 mAh g−1 at 10 A g−1) and excellent cycling stability over 2000 cycles. Hence, rational interfacial designs shed light on the development of organic/inorganic cathodes for advanced AZIBs.