| Antimony is widely used in functional alloy manufacturing, semiconductor materials, battery material and other industrial fields because it has properties of good abrasive resistance, high hardness and chemically stable. Antimony powder has good compressive and wear resistance and excellent lithium intercalation characteristics, which is widely used in lubricants, electrode materials and so on. However, the traditional preparation of antimony powder is mechanical milling method, which have a long period, expensive equipment, more dust in the working environment and harmful to worker etc. Electrochemical deposition has advantages of simple operation, low cost, suitable for large-scale production is an ideal method for the preparation of metal powders. But most of the researches focus on acidic electrolyte which has disadvantages of strong corrosion resistance, poor cycle characteristics and waste processing difficulty. Deep eutectic solvents is a novel green organic solvents, which has wide electrochemical window, high conductivity etc. It is used as electrolyte in the preparation of powder materials with low energy consumption, short cycle, economic and environmental friendly and other advantages, which has important application value and prospect in industry.In this paper, the dissolution properties of Sb2O3 powder in ChCl-EG and the viscosity and conductivity of Sb2O3-ChCl-EG were determined. The electrochemical reduction behavior of Sb2O3 in ChCl-EG was studied by voltammetry. Different particle sizes of antimony powder were prepared from Sb2O3 powder by electrolysis in choline chloride-ethylene glycol (ChCl-EG,1:2molar ratio) eutectic melt at room temperature. The effects of cell voltage, electrolysis time, temperature and other parameters on the composition and morphology of the product were studied. The electrolytic reduction mechanism of Sb2O3 in ChCl-EG was preliminarily explored. The main contents are as follows:The saturated solubility of Sb2O3 in ChCl-EG was 4.18 mM. Testing the viscosity and conductivity of Sb2O3-ChCl-EG, find that as the temperature increases, the viscosity gradually decreases and the conductivity gradually increases.Cyclic voltammetry tests in Sb2O3-ChCl-EG showed that Sb(Ⅲ) is directly reduced to Sb and by analysis calculated reveal that Sb(Ⅲ) reduction in ChCl-EG is a quasi-reversible process controlled by the Sb(Ⅲ) diffusion and as the temperature rises, diffusion coefficient increase, the ED0=32.9 kJ·mol-1. Rhomboidal hexahedral nano antimony powder was prepared by electrodeposition in Sb2O3-ChCl-EG at different voltages and time. With the increase of cell voltage, nano antimony morphology change from self assembly of rod like and wheat like structure to microsphere structure and particles are smaller. With the increase of the electrolysis time, the nano antimony particles become more and more intensive.Linear sweep voltammetry test using Pt cavity microelectrode as the working electrode showed that powder Sb2O3 can be directly reduced to powder antimony in ChCl-EG. With the increase of cell voltage and temperature, the reaction rate of the reduction of Sb2O3 powder is increased and With the extension of electrolysis time, the product is gradually reduced from sheet Sb2O3 to pure Sb powder with three dimensional dendritic structure. It was found that the reduction mechanism of Sb2O3 powder in ChCl-EG was dissolved-electrodeposition mechanism. When electrolysis, Sb2O3 powder was dissolved in ChCl-EG at first and then antimony powder was deposited at cathode because of cell voltage. The new antimony powder will also act as a new cathode, such that the cathode surface area is increased, the rate of the reduction reaction increases. Finally, by comparing the different anode experiments show that the anode area which infiltration into electrolyte bigger, the more quick the reduction reaction.
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