| Silver liquid-like films is formed by silver nanoparticles and coated on liquid substrate. On the one hand, the films exhibit the metallic luster and very high reflectivity. On the other hand, the films are liable to flow and not easy to be fractured. Owing to these special properties, the films can be applied in many filed, such as astronomic telescope and liquid mirror.First of all, using sodium citrate as reducing agent and stabilizer, we obtained the silver nanospheres by reducing silver nitrate. By researching the silver nanoparticles, we found that the particles are composed of fcc silver and at the surface of the particles, the sodium citrate bind with the silver particles, protecting the silver nanoparticles from agglomerating. Furthermore, the silver nanoparticles can be kept from agglomerating for eight days, under room temperature and without sunlight. Additionally, through investigating the influence on the sizes of the silver nanoparticles, it is clear that the sizes of particles increase obviously as the decrease of the first addition of sodium citrate and the increase of reaction time also can enlarge the sizes of the particles within 30min.Secondly, we got different shapes of silver nanoparticles, such as silver nanocubes and silver nanowires, by polyol synthesis method, in which ethylene glycol (EG) serves as both solvent and reducing agent, and poly (vinyl pyrrolidone)(PVP) serves as both stabilizer and agent to control the shape of the particles. By researching the influences of oxygen content, the reaction temperature and the adding approach of raw materials on the shapes of the silver particles, the key factors to obtain the silver nanocubes and the silver nanowires separately are clear. Slowly dripping silver nitrate and PVP together at 160℃, we can get the silver nanocubes and bipyramid with the abundance of oxygen and the silver nanowires with the absence of the oxygen. However, if the temperature can not reach 160℃, the silver nanospheres can be only obtained. Moreover, if dripping silver nitrate quickly and then PVP slowly, we also can get silver nanowires.Finally, using the silver nanospheres, synthesized formerly, and 2,2'-bipyridine (bpy), a kind of organic ligand, the silver reflective liquid-like films have been formed in this study. By studying the structure and the properties of the films, we have a deep insight into the silver liquid-like films. The result shows that the films are composed of two or more than two layers of silver nanoparticles with a good uniformity and the thickness of the films is about 250nm. The films are coated with both sodium citrate and 2,2'-bipyridine, which donating electron from oxygen atoms to silver, or from nitrogen atoms to silver. And the silver content in the films is 90.7% by weight and the films only contains 9.3% organic materials by weight. Furthermore, both the sizes of the silver nanoparticles and the volumes of the liquid substrate have a great effect on the reflectivity of the films. On the one hand, an increase in the nanoparticles sizes will bring about a great improvement in the reflectivity of the films. On the other hand, larger volumes of the liquid substrate which the silver liquid-like films are poured onto will lead to a lower reflectivity of the films. The reason for these phenomena is probably related to the relationships between these two factors and the thickness of the films. In addition, storing in usual environment, the films can keep their good reflectivity for about five days.
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