在四氢呋喃-饱和氯化钠水溶液的两相体系中利用两相法化学合成了双正十六烷氧基二硫代磷酸(DDP)表面修饰的Cu纳米颗粒.系统探讨了不同因素对制备Cu纳米颗粒的影响,并采用透射电子显微镜(TEM)比较分析不同还原剂的用量、Cu^2+浓度、修饰剂双正十六烷氧基二硫代磷酸铵盐(ADDP)和Cu^2+的物质的量之比对Cu纳米颗粒粒径及分布的影响;通过红外光谱仪(IR)、X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)等测试技术对优化条件下所合成的铜纳米颗粒进行了结构表征.结果表明,合成粒径细小、分布均匀的铜纳米颗粒的工艺条件为pH值在12左右,反应温度高于30℃,铜离子浓度小于0.05m01.L^-1,NaBH4与Cu^2+的物质的量之比在8:1到12:1之间,ADDP和Cu^2+的物质的量之比为2:1和2.5:1;所制备的铜纳米颗粒是由无定形的金属Cu无机纳米核及通过化学键键合在其表面的DDP分子所组成,并且修饰剂在反应前后结构没发生变化.
Di-n-hexadecyldithiophosphate (DDP) capped Cu nanoparticles were chemically synthesized in a two-phase system including tetrahydrofuran and saturated NaCI solution by using two-phase method. Various factors, which affected preparation of Cu nanoparticles were discussed systematically, and transmission electron microscopy (TEM) was used to analyze the effects of the amount of reducing agent, concentration of Cu^2+, molar ratio of ammonium di-n-hexadecyldithiophosphate (ADDP) to Cu^2+ on the size and distribu- tion of the as-prepared Cu nanoparticles. The structure of Cu nanoparticles obtained under the optimal pre- paration conditions was investigated by infrared spectroscopy (IR), X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS). The results showed that when pH value of solution was about 12, reaction temperature was above 30℃, molar ratio of NaBH4/Cu^2+ was between 8 : 1 to 12 : 1, concentration of Cu^2+ was below 0.05 mol·L^-1, and molar ratio of ADDP/Cu^2+ was 2 : 1 and 2.5 : 1, mono-dispersed and superfine DDP capped Cu nanoparticles were obtained. The prepared Cu nanoparticles consist of an amorphous nano-Cu core and a layer of DDP chemically absorbed on its surface, and the structure of modifier DDP was not changed after reaction.