Reduced Graphene Oxide-Anchored Manganese Hexacyanoferrate with Low Interstitial H 2 O for Superior Sodium-Ion Batteries.

Low cost manganese hexacyanoferrate (NMHCF) possesses some favorable advantages including high theoretical capacity, ease of preparation and robust open channels that enables faster Na+ diffusion kinetics. However, high lattice water and low electronic conductivity are the main bottlenecks to their pragmatic realization. Here, we present a strategy by anchoring NMHCF on RGO to alleviate these problems. Accordingly, the composite yields a specific discharge capacity of 161/121 mAh g-1 at the current density of 20/200 mA g-1. Moreover, the sodiation process is well revealed by Ex-situ XRD, EIS and car-parrinello molecular dynamics simulations. At a rate of 20 mA g-1, the hard carbon//NMHCF/RGO full cell affords a stable discharge capacity of 84 mAh g-1 (based on the weights of cathode mass) over 50 cycles, thus highlighting NMHCF/RGO an alternative cathode for sodium-ion batteries.