银纳米膜的电化学制备方法及性能表征

采用电沉积方法在表面活性剂与电解液的界面上制备了银纳米膜。通过对甲磺酸银体系和硝酸银体系中纳米银膜的电沉积速率及纳米银膜颗粒进行比较发现，相同条件下硝酸银体系得到的纳米膜晶粒粒径比较小，膜的生长速率较快。选定硝酸银体系为电沉积体系。考察了槽压、电解液的浓度和温度及溶液的pH值对制备银纳米膜的影响，确立了制备银纳米膜的最佳工艺条件为硝酸银浓度5mmol/L，槽压4V，pH3.0,硬脂酸的质量浓度0.2g/L。实验表明，最佳工艺条件下制备的银纳米膜晶粒粒径均匀，平均粒径在20nm左右，近似球形。本方法制备的银纳米膜将在非线性光学材料方面得到应用。

Preparation of nanometer Ag film by electro-deposition method

Nanometer Ag film is deposited on the interface of surface active agent and electrolyte by electro-deposition process.By comparing the electro-deposition rate and the particle-size of nanometer Ag film prepared by methyl sulfonic acid silver system with those of nanometer Ag film prepared by nitrate silver system under the same conditions,it is found that the particle-size of nanometer Ag film electro-deposited with nitrate silver is smaller and the growth rate of the nitrate silver nanometer film is faster.During the experiment,the silver grain was smaller and the distribution was more uniform in the nitrate silver electrolyte than in the methylsulfic silver electrolyte.That's the reason why the nitrate silver system is selected as the electro-deposition system.For the nitrate silver electrolyte,the depositing current increases with the increase of concentration and voltage.The effect of cell voltage,concentration and temperature of electrolyte and pH value of the solution on nanometer film preparation has been analyzed.The optimal conditions on which the needed nanometer film was prepared: the concentration of the nitrate silver is 5 mmol/L,the voltage is 4 V,the pH value is 3.0 and the concentration of stearic acid is 0.2 g/L.The experiment indicates that grain diameter of Ag nanometer film deposited under the optimum conditions is about 20 nm on average and the grain shape is roughly spherical.The Ag nanometer film prepared with this method can be used in nonlinear optical material.