Zulipiya Shadike, Ding-Ren Shi, Tian-Wang, Ming-Hui Cao, Shi-Feng Yang, Jian Chen*, Zheng-Wen Fu*,Long life and high-rate Berlin green FeFe(CN)₆ cathode material for a non-aqueous potassium-ion battery. J. Mater. Chem. A, 2017, 5, 6393-6398

Abstract

A high-quality sized FeFe(CN)6 was synthesized as a cathode material for a non-aqueous potassium-ion battery. The electrode delivered a reversible capacity of 124 mAh/g at the current rate of 0.5C and still retained a reversible capacity of 93 mAh/g after 500 cycles at 5C with a columbic efficiency of 100%. Structural evolution and redox couples of low and high spin FeIII/FeII were investigated by ex situ X-ray diffraction, Mössbauer spectroscopy, and X-ray photoelectric spectroscopy. The negligible volume change during the electrochemical process should be responsible for the excellent cyclic stability.