Structure optimization of Prussian blue analogue cathode materials for advanced sodium ion batteries

A structure optimized Prussian blue analogue Na1.76Ni0.12Mn0.88[Fe(CN)6]0.98 (PBMN) is synthesized and investigated. Coexistence of inactive Ni(2+) (Fe-C≡N-Ni group) with active Mn(2+/3+) (Fe-C≡N-Mn group) balances the structural disturbances caused by the redox reactions. This cathode material exhibits particularly excellent cycle life with high capacity (118.2 mA h g(-1)).