微米银粉的正交实验法制备与表征

研究了以抗坏血酸为还原剂的液相还原法制备球形微米银粉时的主要因素对振实密度和形貌的影响。实验表明,酸性条件下制备的微米银粉分散性较好。正交实验表明,对银粉振实密度的影响大小的因素依次为底液pH、硝酸银浓度、分散剂PVP用量和实验温度。经过对银粉进行粒度、SEM和XRD等测定表征发现,优化条件下可制备得到振实密度为4.2 g/cm~3,平均粒径2.5μm,分散性良好的类球形银粉。

Synthesis of Micro-sized Silver Powder by Orthogonal Design and Characterization

Micro-sized silver powders were prepared from the aqueous solution of AgNO3 by using ascorbic acid as a reductive agent. The particle size, morphology and crystalline of silver powders were characterized by particle size analysis, SEM and XRD, and an orthogonal experiment was conducted to optimize the preparative process. The results showed that the factors influencing the tap density and morphology of the resulting powders mainly include pH value, the initial concentration of AgNO3, the dosage of the dispersant and the reaction temperature. Among them, pH value is the most important factor. Near-spherical and well-dispersed silver powders with a tap density of 4.2 g/cm3 and an average particle size of 2.5 μm, were obtained in our Lab under the optimum preparative conditions.