Controllable Synthesis Of Silver Nanowire And Research On Its Application

One step polyol method is a relatively mature technique for the synthesis of silver nanowires.The main problems of this method are:1)The size of silver nanowires is difficult to control accurately;2)The study of reaction volume amplification is not enough;3)The washing of mother liquor and efficient separation and purification of silver nanowires are difficult.In this paper,silver nanowires were synthesized by one step polyol method.The effects of metal cation type control agent,inorganic anion type control agent and composite control agent on the size of silver nanowires were studied,the expected size products were synthesized and the action mechanism of different chemical control agents was analyzed.The effect of volume amplification on the size and quality of the product was studied.Experimental study on washing and separation of mother liquor was carried out.According to the properties of silver nanowires with different sizes,the potential applications of silver nanowires were studied.First,the silver nano rod was used as the conductive phase of silver paste for screen printing,and the properties of the conductive film prepared by silver paste were investigated.The second step is to try to substitute silver micro powder for silver zinc battery and preliminary study on Microstructure and charging performance of silver nanowire electrode and silver micro powder electrode was finished.The results show that the type of chemical control agent has a great influence on the size of silver nanowires.The mechanism of the action of cationic and anionic agents on the nucleation and growth of silver nanowires is different.The addition of cationic chemical agents(such as Mn²⁺,Ni²⁺,Co²⁺,etc.)alone tends to make the silver nanowires longer and coarser.The addition of anionic chemical agents(such as OH^-,CO₃^2-,SO₄^2-,etc.)tends to shorten the length of the wire,and even to produce silver nanoparticles.The suitable metal cation/inorganic anion composite controller can be used to control the length and diameter of silver nanowires in a certain range.The purpose of washing is to remove PVP and other organic compounds in the mother liquor of AgNW reaction.The results show that the dilution and heating can reduce the viscosity of mother liquor and facilitate the removal of organic matter.Based on cost and efficiency consideration,deionized water dilution reaction mother liquor was selected.It was found that the washing times had great influence on reducing the content of PVP and EG in the reaction mother liquor and After four times of washing,the content of organic compounds in the product is very low.Efficient separation of AgNW and AgNP in dispersion solution can be achieved by pressure filtration and pure AgNW can be obtained by three times press filtration.Silver paste made by silver nanorod screen printing can effectively reduce the square resistance and improve the conductivity of the film.After the wet film printed was sintered at 80^oC and 120^oC,the square resistance of the film was reduced obviously.The residual PVP on silver nanowires has a great influence on the charging effect of positive electrode of zinc silver battery.The PVP on the synthesized silver nano rough wire is easier to remove by multiple washing methods.The pure silver nanowires were prepared by pressing forming at relatively small pressures?such as 0.5MPa?and sintered at lower temperatures?such as 200 ^oC?and the specific surface area of the electrode is larger,which is beneficial to the improvement of the formation effect.Compared with the micron sized silver electrode,the generation from long silver nanowie electrode to silver oxide increased by about 29%,which preliminarily indicated that the positive electrode of zinc silver battery prepared by silver nanowires may provide the battery with greater specific energy.