Enhancing the electrochemical performance of Prussian blue analogue cathodes through mild heat treatment for sodium-ion batteries

Abstract

Prussian blue analogues (PBAs) are potential cathodes for sodium-ion batteries (SIBs). However, aqueous synthesis introduces lattice water, causing side reactions and structural degradation, impairing electrochemical performance. In this study, we developed a mild heat treatment method to reduce lattice water in PBAs without structural alteration or phase transitions. Consequently, the treated samples exhibited smaller voltage hysteresis and improved rate performance, and maintained over 80% capacity after 750 cycles.