(1. 东北大学 材料各向异性与织构教育部重点实验室，沈阳 110819；
2. 东北大学 中荷生物医学与信息工程学院，沈阳 110169)
摘 要: 研究以抗坏血酸为还原剂、采用液相还原法制备微纳米铜粉过程中pH值、混合方式和混合速率对铜粉形貌和粒径的影响。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对合成产物进行表征。结果表明：液相反应溶液体系的pH值对反应产物的物相及其形貌有决定性的影响；当pH值控制为3~8时，还原产物为纯铜相；当pH为9~12时，产物是金属Cu与Cu2O混合相；当pH值高于13时，还原产物为Cu2O相；反向滴定即CuSO4溶液向抗坏血酸溶液中滴定时制备的铜粉颗粒粗大呈微米级，正向滴定获得的铜粉细小呈亚微米级；以快速倾倒方式获得的铜粉颗粒尺寸分布窄且分散性良好，以慢速滴注获得的铜粉的尺寸与形状与前者的相近，但分布不均匀。
关键字: 铜粉；抗坏血酸；混合方式；混合速率
（1. Key Laboratory of Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819, China;
2. Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang 110169, China）
Abstract:The micro/nano copper powders were prepared by liquid phase reduction using ascorbic acid as reducing agent. Meanwhile, the effects of pH value, mixing ways and mixing rates on the characteristics of copper powders were discussed. The as-synthesized products were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results show that the pH value of reactive solution system has key effect on phase type and morphology of the products. Pure Cu phase is obtained in the pH range of 3-8, and then Cu and Cu2O mixed phases are obtained, finally it is pure Cu2O as the pH exceeds 13. The particle size of copper powders prepared by reverse titration is large and in micron grade. Conversely, it is small and in submicron size. The distribution of Cu powder size obtained by dump is narrow and well dispersed compared to that of the powder prepared by slow dripping.
Key words: Cu powder; ascorbic acid; mixing mode; mixing rate
