Anxing Zhou: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Liwei Jiang: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Jinming Yue: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Yuxin Tong: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Qiangqiang Zhang: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Zejing Lin: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Binghang Liu: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Chuan Wu: School of Materials Science and Engineering , Beijing Institute of Technology , Beijing 100081 China. ORCID
Liumin Suo: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China. ORCID
Yong-Sheng Hu: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China. ORCID
Hong Li: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China. ORCID
Liquan Chen: Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , China.
Prussian blue analogues (PBAs) are considered to be ideal multivalent cation host materials due to their unique open-framework structure. In aqueous solution, however, the PBAs' cathodes have a low reversible capacity limited by the single electrochemical group Fe(CN) and high crystal water content. They also suffer from fast cycle fading, resulting from significant oxygen/hydrogen evolution and cathode dissolution. In this work, a high-capacity PBA-type FeFe(CN) cathode with double transition metal redox sites is successfully demonstrated in 5 m Al(CFSO) Water-in-Salt electrolyte (Al-WISE). Due to Al-WISE having a wide electrochemical window (2.65 V) and low dissolution of the cathode, our PBA cathode exhibits a high discharge capacity of 116 mAh/g and the superior cycle stability >100 cycles with capacity fading of 0.39% per cycle.
