TY  - JOUR
AU  - Li, Zhuxin
AU  - Liu, Tingting
AU  - Meng, Ruijin
AU  - Gao, Lujie
AU  - Zou, Yiping
AU  - Peng, Peng
AU  - Shao, Yuying
AU  - Liang, Xiao
PY  - 2021
TI  - Insights into the Structure Stability of Prussian Blue for Aqueous Zinc Ion Batteries
JO  - Energy & Environmental Materials
SN  - 2575-0348
SP  - 111
EP  - 116
VL  - 4
IS  - 1
AB  - The reversible storage of Zn2+ ions in Prussian blue analogues with typical aqueous solution was challenged by fast degradation and poor coulombic efficiency, while the mechanism is yet to be uncovered. This study correlates the performance of the nickel hexacyanoferrate to the dynamics of H2O in the electrolyte and the associated phase stability of the electrode. It demonstrates severe Ni dissolution in conventional diluted aqueous electrolyte (1 M ZnSO4 or 1 M Zn(TFSI)2), leading to structure collapse with the formation of an electrochemical inert phase. This is regarded as the descriptor for the fast decay of nickel hexacyanoferrate in diluted aqueous electrolyte. However, a well-preserved open framework for zinc storage was obtained in concentrated aqueous electrolyte (1 M Zn(TFSI)2 + 21 M LiTFSI) —the H2O activity is highly suppressed by extensive coordination—thus, reversible capacity of 60.2 mAh g−1 over 1600 cycles could be delivered.
UR  - https://doi.org/10.1002/eem2.12108
DO  - 10.1002/eem2.12108