KCoFe(CN)/rGO with Dual-Active Sodium Ion Storage Site as Superior Anode for Sodium Ion Battery.

The unique and open large frame structures of prussian blue analogues (PBA) enables it for accommodating a large number of cations (Na, K, Ca, etc.), thus, PBA are considered as promising electrode materials for the rechargeable battery. However, due to the chemical composition, there are still many alkaline metal ions in the gap within the framework, which puts multivalent metals in PBA in a low valence state and affects the sodium storage performance.