地榆-纳米银复合物的制备与表征

Preparation and characterization of Sanguisorbae Radix/nano-silver composites

目的以地榆为还原剂及分散剂还原硝酸银溶液制备地榆-纳米银复合物,并对其进行表征。方法以地榆-纳米银复合物的吸光度为指标,考察地榆粉末提取时间、地榆提取液加入量、AgNO3溶液浓度、合成温度等对地榆-纳米银复合物形成的影响,并筛选最佳合成条件。采用透射电子显微镜(TEM)、X射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、动态激光散射(DLS)对地榆-纳米银复合物的理化性质进行表征。结果地榆粉末煮沸15 min,地榆提取液(0.1 g/mL)与1 mmol/L AgNO3溶液体积比为1∶10,25℃反应1 h制备地榆-纳米银复合物条件最佳,所得地榆-纳米银复合物形状近似球形,平均粒径约为21 nm,分布均匀、性质稳定。结论地榆-纳米银复合物制备方法稳定、可行。

Objective To synthesize and characterize Sanguisorbae Radix/nano-silver composites by reduction of silver nitrate solution using Sanguisorbae Radix as reducing agent and dispersant. Methods Taking the absorbance of UV-visible spectroscopy of Sanguisorbae Radix/nano-silver composites as index to study the influence of different factors, such as extracting time of Sanguisorbae Radix powder, reaction temperature of synthesis, volume of Sanguisorbae Radix extract, and concentration of AgNO3, on the formation of nano-silver composites and to optimize the conditions. TEM, XRD, FT-IR, and DLS could be used to characterize the physicochemical properties of Sanguisorbae Radix/nano-silver composites. Results The optimum conditions were as follows： the boiling time of Sanguisorbae Radix powder was 15 min, the volume ratio of 0.1 g/mL Sanguisorbae Radix extract and 1 mmol/L AgNO3 was 1∶10, the resultant temperature was 25 ℃, and the reaction time was 1 h, the Sanguisorbae Radix/nano-silver composites obtained were approximately spherical in shape with the mean size about 21 nm in good uniformity and stability. Conclusion The preparation of Sanguisorbae Radix/nano-silver composites is stable and feasible.