Porous Carbon‐Coated Fe‐Doped MnO as High‐Performance Cathode for Aqueous Zinc Ion Batteries

Ion doping is a feasible approach to enhance the stability and cycling performance of manganese‐based materials. However, limited research has been conducted on Fe‐doped manganese‐based oxides. The present study represents the first successful synthesis of a composite material, namely porous carbon‐coated Fe‐doped MnO (Fe‐MnO/C), achieved through annealing FeMn‐based metal‐organic frameworks. The electrochemical performance is enhanced by Fe doping, as the presence of MnOFe bonds facilitates charge transfer and mitigates structural collapse, thereby resulting in improved rate capability and cycling stability. The Fe‐MnO/C‐3 cathode achieves a maximum energy density of 249.6 Wh kg −1 at a power density of 130.6 W kg −1 and demonstrates a high specific capacity of 134 mAh g −1 even after undergoing 800 cycles at 1.0 A g −1 . The study presents a cost‐effective and convenient approach to fabricate a high‐performance cathode for aqueous zinc‐ion batteries.