Double strategies of graphene-coated potassium ferrate follow-up encapsulation of chitosan for enhanced the conductivity and stability of ferrate (VI) battery

The poor conductivity and stability of ferrate salts are key factors that hinder the application of super‑iron batteries. In the paper, double strategies of graphene-coated potassium ferrate follow-up encapsulation of chitosan were proposed and implemented for enhanced the conductivity and stability of ferrate (VI) battery. The characterization and electrochemistry of modified ferrates and battery were performed in the lab works. The graphene oxide (GO)-coated and follow-up chitosan(CS)-encapsulated ferrates were successfully fabricated by a confirming of SEM images. The electrochemical and cell performance of the modified ferrates was tested and evaluated in a 10 M KOH solution using a button cell configuration. Notably, the GO-CS modified potassium ferrate exhibited superior cell performance and stability in high current discharge. Electrochemical impedance spectroscopy (EIS) reveals that the 1.75 wt% GO-CS coated sample exhibits the lowest charge transfer impedance. Discharge tests indicate that this sample outperforms the uncoated ferrate at 100 Ω while showing comparable performance at 200 Ω. UV analysis further showed that the 1.75 wt% GO-CS coating sample achieved optimal phenol degradation at both 15 mg and 20 mg doses, while the 1.05 wt% and 2.45 wt% coatings performed poorly.