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

In this study, potassium titanium hexacyanoferrate (K0.3Ti0.75Fe0.25[Fe(CN)6]0.95·2.8H2O) 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.