Ni-Containing Electrolytes for Superior Zinc-Ion Aqueous Batteries with Zinc Hexacyanoferrate Cathodes.

A one-step coprecipitation process is designed to synthesize zinc hexacyanoferrate (ZnHCF) cathodes in aqueous zinc-ion batteries (ZIBs). The morphology of the cathode is influenced by the concentration of the precursor solution and valence of iron ions. The rhombohedral ZnHCF sample exhibits high crystallinity on the microscale in the cut-angle cubic structure, whereas Na-rich NaZnHCF contains many interstitial water molecules in the rhombic nanoplates.