Preparation And Electrochemical Properties Of Nano-silver Powder Study

Nanosilver powder has been widely applied in the electrode materials due to its small grainsize, large specific surface areas, many active sites on the surface, and high conductivity.In this paper, nanosilver powders were prepared by chemical reduction in liquid phase and reverse microemulsion, repectively. For the preparation of nanosilver powder by the chemical reduction in liquid phase, the category of reducing agent, the initial Ag~+ concentration, reaction temperature, and PVP concentration were investigated. The optimized preparation conditions were acquired as listed below. The reducing agent is sodium borohydride, the initial Ag~+ concentration of is 0.2mol/L, the reaction temperature is 45℃, PVP concentration is 0.2 mol/L. For the one synthezied by reverse microemulsion, the initial Ag~+concentration, reaction temperature, the ratio of water and surfactant PVP, and the dosage of cosurfactant (n-hexylol alcohol) were studied. The optimal conditions gained were as follows. The initial Ag~+ concentration is 0.1 mol/L, the reaction temperature of is in the range of 40 to 50℃, the ratio of water and surfactant is 1, the dosage of n-hexyl alcohol is 0.2 mol.The cycle performance of the batterys of double electrodes which were made by nanosilver and the nanosilver-graphitecarbon composites were tested at small rate. The nanosilver and the nanosilvergraphitecarbon composites were prepared by chemical reduction in liquid phase and reverse microemulsion in our experiments. The results indicated that the nanosilver electrodes held high specific capacity and favorable cycle performance, and the electrochemical cycle performance of the nanosilver-graphitecarbon composites after the deposition of nanosilver particles was improved greatly and the electrochemical performance of the lithium ion battery was advanced effectively.