Potassium titanium hexacyanoferrate as a cathode material for potassium-ion batteries

In this study, potassium titanium hexacyanoferrate (K 0.3 Ti 0.75 Fe 0.25 [Fe(CN) 6 ] 0.95 ·2.8H 2 O) was obtained by a simple co-precipitation and used as a cathode material in potassium-ion batteries (KIBs) for the first time. The reversible redox couples of Fe and Ti could provide 136.7 mA h g −1 at 50 mA g −1 and 113 mA h g −1 at 100 mA g −1 in the first discharge. Considering that this material is easy to synthesize, with low cost and good electrochemical performance , our results suggest the possible development of KIBs as cathodes and future research into rechargeable KIBs.