binder-free copper hexacyanoferrate electrode prepared by pulse galvanostatic electrochemical deposition for aqueous-based al-ion batteries

Copper hexacyanoferrate (cuhcf) nanoparticles with tunnel-like prussian blue structure were deposited on a graphite substrate via pulse galvanostatic electrodeposition at 25 ma cm-2 with two 0.1 speriods of on/off-time. the prepared electrodereversibly showed the intercalation/de-intercalation ability of al ions in aqueous solution. the crystal structure of the as-prepared cuhcf film was characterized by x-ray diffraction (xrd) analysis. the surface morphology of the film was examined by a field-emission scanning electron microscope (fesem). moreover, the electrochemical energy storage performance of the prepared binder-free electrode was inspected by cyclic voltammetry (cv) and galvanostatic charge-discharge (gcd) measurements at various rates in aqueous-based aluminum sulfate electrolyte. the cuhcf was verified that canbe a promising cathode material for the aqueous alion batteries. the prepared cuhcf electrode exhibited a high specific capacity of 77.7 mah g1 and a good rate capability with 67.1% capacitance retention rate at a current density of 50 ma g1and 400 ma g1, respectively. furthermore, after 400 cycles at 400 ma g1, the electrode showed a good cycle performance with a capacity retention rate of 74.4%.