Fig. 3: The structural evolution and charge compensation mechanism of the KFeC2O4F cathode.
From: A fluoroxalate cathode material for potassium-ion batteries with ultra-long cyclability
a A typical galvanometric charging–discharging curve of a stabilized half cell in the window of 1.5–4.6 V at a current density of 0.1 A g−1 and corresponding synchrotron Fe K-edge XANES during charging b and discharging c, and Fe EXAFS during charging d and discharging e. f Ex situ XRD of KFeC2O4F upon K ions extraction and reinsertion and the highlighted characteristic peaks in 22.5–23.3° corresponding to (200) plane g and 28.3–29.2° corresponding to (221) plane h.
