多元醇法制备银纳米线的工艺优化及结构表征

Optimazition of Polyol Process to Prepare Silver Nanowire Material and Its Structure Characterization

采用多元醇法制备银纳米线,分别通过单因素分析和正交试验设计对表面活性剂聚乙烯吡咯烷酮(PVP)分子量及用量、反应温度等工艺条件进行优化,并表征了结构。研究结果表明:PVP分子量影响银核特定晶面的被包覆速率,反应温度影响银还原及线生长速率,并与PVP分子量存在适配关系,PVP与银源的质量比(P∶A值)对产物长径比影响最大;反应温度为150℃,PVP分子量为360000,P∶A值为1∶1,制备出的银纳米线平均直径为80nm,平均长度约25μm,其长径比可达320;将不同分子量PVP混合使用,可将线直径减小到均匀的60nm,长径比可进一步提高到600。

Silver nanowires were prepared by apolyol process,during which the parameters such as the molecular weight of surfactant(polyvinylpyrrolidone,PVP),surfactant content and reaction temperature were optimized with single factor and orthogonal experiments.Microstructure of the as-prepared silver nanowires was also characterized.The results show that the molecular weight of PVP affects the covering rate on the specific crystal face of silver nucleus,and that the reaction temperature affects the process of reduction reaction and the growth rate of the nanowires,both of which have a matching relationship.The mass ratio of PVP to AgNO3(value of P∶A)exhibts a significant impact on the aspect ratio of silver nanowires.Silver nanowires with average diameter of 80 nm,length of about 25μm and the corresponding aspect ratio of 320 were prepared under the optimum parameters:reaction temperature of 150℃,PVP molecular weight of 360000 and P∶A value of 1∶1.In addition,when the mixed molecular weight of PVP are used,average diameter of silver nanowires decreases to 60 nm and the corresponding aspect ratio increases to 600.