KxFeO2 As Electrode Material for K-Ion Batteries

Abstract

To meet future energy demands, developing beyond-lithium energy storage technologies have become a major part of global research activities. Potassium-ion batteries (KIBs) represent a promising technology thanks to their chemical and economic advantages1–3. The majority of the work on layered transition oxide was done on the KxMnO2 family4,5 due to their safety and price advantage.Interestingly, KFeO2 structure is not a layered structure as for LiFeO2 or NaFeO2; this structure is defined as FeO4 tetrahedral linked by their corners. In electrochemistry, a reversible capacity of 60 mAh/g (for 0.3K+) was delivers6.In our presentation, we will detail the electrochemical behaviour of KFeO2 and discuss the structure/properties relationship of this family of materials, showing the interest in the exploration of such a system. Xu, Y. et al. 2023 roadmap for potassium-ion batteries. J. Phys. Energy 5, 021502 (2023).Tian, Y. et al. Promises and Challenges of Next-Generation “Beyond Li-ion” Batteries for Electric Vehicles and Grid Decarbonization. Chem. Rev. 121, 1623–1669 (2021).Zhang, W., Liu, Y. & Guo, Z. Approaching high-performance potassium-ion batteries via advanced design strategies and engineering. Sci. Adv. 5, eaav7412 (2019).Kim, H. et al. Investigation of Potassium Storage in Layered P3-Type K0.5MnO2 Cathode. Adv. Mater. 29, 1702480 (2017).Liu, C., Luo, S., Huang, H., Zhai, Y. & Wang, Z. Layered potassium-deficient P2- and P3-type cathode materials KxMnO2 for K-ion batteries. Chem. Eng. J. 356, 53–59 (2019).Han, S. C., Park, W. B., Sohn, K.-S. & Pyo, M. KFeO2 with corner-shared FeO4 frameworks as a new type of cathode material in potassium-ion batteries. J. Solid State Electrochem. 23, 3135–3143 (2019).