Silver nanoparticles due to the small size, large surface area, high surface activity, easy to reunite, thus affecting its stability and its light, electricity and other applications. Silver Nanoparticle In order to avoid agglomeration of silver nanoparticles, the choice of adding surfactants and reaction systems in the reaction system has become a key technology for the preparation of silver nanoparticles. In this paper, chemical reduction method, silver nitrate as the reaction material, the choice of sodium oleate and KH-550 as the surfactant, Silver Nanoparticle N, N-dimethylformamide, ethylene glycol, ethanol as the reducing agent, by changing the reaction conditions, Silver nanoparticles with good morphology and good crystallinity were prepared. The effects of different reaction conditions on the synthesis of silver nanoparticles were analyzed by UV - Vis spectrophotometer, Silver Nanoparticle transmission electron microscopy and X - ray diffraction. The silver nanoparticles were synthesized by using sodium oleate as the surfactant and water (DMF as reducing agent), ethylene glycol and ethanol as solvent. The results show that the water sol of silver nanoparticles can be formed by changing the reaction time, reaction temperature and reducing agent dosage in the presence of water as solvent. The kinetic process of the formation of silver nanoparticles by various factors is studied and the reaction temperature , The amount of reducing agent and other factors on the synthesis of silver nanoparticles of the optical properties, Silver Nanoparticle size and morphology have a significant impact. The effects of reaction temperature, reaction time and reactant ratio on the morphology, size and optical properties of the silver nanoparticles were studied by changing the reaction conditions. The effects of reaction temperature, reaction time and reactant ratio on the morphology, size and optical properties were investigated. When the concentration of the reactants decreases, Silver Nanoparticle the process of preparing the silver nanoparticles in the ethylene glycol system leads to the transition from floc to the emulsion. The critical concentration of silver nitrate is 2 × 10-3mol / L, while the ethanol system There is no such change. Using KH-550 as the surfactant, Silver Nanoparticle N, N-dimethylformamide as solvent and reducing agent to synthesize silver nanoparticles. The results showed that KH-550 had a better effect on the surface of silver nanoparticles, Silver Nanoparticle and the temperature was increased and the reaction time was prolonged and the reaction rate was accelerated. The ratio of KH-550 to silver nitrate and reactant concentration on the growth of silver nanoparticles Large; at 60 ℃ for 1min ~ 4h reaction can be observed in the silver nanoparticles from spherical to non-spherical morphological transformation process.
Silver nanoparticles and the prepared silver nanoparticles. The method comprises the following steps: 1) mixing the acid solution of chitosan with silver nitrate solution to obtain a mixed solution, wherein the degree of deacetylation of chitosan is greater than or equal to 70 %, Average molecular weight of less than or equal to 20,000, Silver Nanoparticle in which the concentration of chitosan is 0.001 to 0.05 wt%, the concentration of silver nitrate is 0.01 to 23.5 mM, 2) the pH is adjusted to 3.0 to 5.0, Under irradiation. The silver nanoparticles prepared by the method of the invention have the advantages of small average particle size, Silver Nanoparticle good homogeneity, high solid content and good water solubility and biocompatibility. The preparation method of the invention can also easily control the particle size distribution Uniform silver nanoparticles.