真空冷冻干燥法制备纳米铜粉的实验研究  

Synthesis and Characterization of Vacuum Freeze-Dried Copper Nano-Powder

作　　者：彭润玲[1] 韩少星 曾群锋[2] 刘鹏[1] 刘官[1] 

机构地区：[1]西安工业大学机电工程学院,西安710021 [2]西安交通大学现代设计及转子轴承系统教育部重点实验室,西安710049

出　　处：《真空科学与技术学报》2016年第2期217-222,共6页Chinese Journal of Vacuum Science and Technology

基　　金：陕西省教育厅专项科研计划项目(14JK1334);国家自然科学基金项目(51305331);江西省铜钨新材料重点实验室开放基金项目(2013-KLP-03)

摘　　要：为了提高纳米铜粉的分散性,以五水硫酸铜和次亚磷酸钠为原料,采用三种不同的冻结方式：-55℃直接冷冻、抽真空快速冷冻、液氮急速冷冻,用真空冷冻干燥法制备了纳米铜粉。通过透射电子显微镜、X射线衍射仪对产物的粒径、纯度进行了检测。结果表明,冻干法制备的粉体纯度较高、颗粒细小、形状规则、无硬团聚;三种冻结方式制备的样品粒径分别为8-45 nm,4-25 nm,3-20 nm。采用表面修饰法对粉体进行表面改性,相比市售纳米铜粉,冻干纳米铜粉改性后作为润滑油添加剂的分散稳定性较好,采用抽真空冻结的纳米铜粉最好,其油样在18 h后能稳定分散,9天后仅有10%的沉降、分层现象。The stably dispersed Cu nano-powders were synthesized by freeze-drying the precursor solution of CuSO4·5H2O and NaH2PO2 in-55℃ cold-trap,in vacuum,and in liquid nitrogen.The Cu nano-powders were characterized with X-ray diffraction and transmission electron microscopy（TEM）.The results show that no conglomeration occurred in the highly dispersed Cu-powders freeze-dried in the three methods.The sizes of the Cu-powders freeze-dried in-55℃ cold-trap,in vacuum and by liquid nitrogen lie in the ranges of 8-45 nm,4-25 nm and3-20 nm,respectively.The cold-trap freeze dried Cu-powder with regular nano-particles is purer than the other two.In addition,the surface modification markedly improves the dispersion of all the Cu-powders.The cold-trap freeze-dried Cu-powder outperforms the commercial Cu-powder as lubricant additives because of better dispersion stability.The vacuum freeze-dried Cu-powder displays the best property.For instance,it can be dispersed in oil within 18 h,and only 10%were involved in sedimentation and stratification in exposure to air for 9 days.

关 键 词：纳米铜 真空冷冻干燥 冻结方式 分散性 

分 类 号：TQ131.210[化学工程—无机化工]