Study On Preparation And Electrochemical Properties Of Ferrate (â…¥) Cathode

Ferrate as anode is ideal material in stead of the one of alkaline batteries because of its high theoretical discharge capacity and friendly environment. High purity, stability and increase of actual discharge capacity of ferrate have great significant to research ferrate battery. Therefore, the preparation of highly pure ferrate and the increase of actual discharge capacity were investigated in this paper. The technics of preparation of ferrate was improved and simplified compared with previous tedious preparation . There is the clear difference between actual discharge capacity and theoretical discharge capacity. The factor affecting the electrochemical performance of ferrate and the mechanism of improved electrochemical performance owing to additive were investigated in this paper. This paper contains 7 chapters as follows:In the first chapter, the structure, character, application and development history of ferrate and its development as anode were reviewed. The significance of choosing this subject and related scientific problem needed to be solved were raised.In the second chapter, K₂FeO₄ was prepared by hypochlorite oxidation method and BaFeO₄ was synthesized by reaction of K₂FeO₄ with Ba(OH)₂. The microstructure of potassium ferrate and barium ferrate were measured by IR, XRD and SEM. The IR spectroscopy and XRD spectroscopy confirmed that the major component of the product were potassium ferrate and barium ferrate. The K₂FeO₄ particles are long and thin parcel, the BaFeO₄ particles are granular with a diameter of about 50-100 nm .In the third chapter, the purity of ferrate was determined by chromate oxidation method and EDTA titration method. The result indicated the purity of K₂FeO₄ and BaFeO₄ is 97.7% and 96.7% respectively.In the fourth chapter, the preparation of potassium ferrate was investigated with respect to reaction temperature, reaction duration, the ratio of iron nitrate in reaction ,the best concentration of KOH in recrystallization. The results showed that the optimum condition of...