A Na-Rich Nanocomposite of Na1.83Ni0.12Mn0.88Fe (CN)(6)/RGO as Cathode for Superior Performance Sodium-Ion Batteries

Prussian blue analogs are receiving intense attention due to their high theoretical energy density and low cost, but their real applications are still hampered by poor electronic conductivity and cycling stability. Here, Na1.83Ni0.12Mn0.88Fe(CN)(6) wrapped with graphene was synthesized by a facile co-precipitation method. The existence of RGO not only significantly increases the conductivity of the cathode, but also makes the framework much more robust during long cycling process. As the cathode, the Na1.83Ni0.12Mn0.88Fe(CN)(6)/RGO is able to deliver a high initial discharge capacity of 120 mA h g(-1) at a current density of 20 mA g(-1) with superior capacity retention of 96.7% after 100 cycles. Even at a current density of 1000 mA g(-1), the cell still delivers a capacity of 86 mA h g(-1), indicating outstanding rate capability. The results and the facile synthesis method enable Na1.83Ni0.12Mn0.88Fe(CN)(6)/RGO to the competitive for a future energy storage system.