PVP对液相还原法制备微米级银粉颗粒性能的影响

摘要

采用液相还原法,硝酸银为银源,抗坏血酸为还原剂,聚乙烯吡咯烷酮(PVP)为分散剂及保护剂制备超细银粉.考察PVP添加量以及添加方式对超细银粉形貌、粒径及分散性能的影响,通过SEM,XRD以及激光粒度仪等检测手段对超细银粉产品进行表征.结果表明:随着反应体系中PVP用量的增加,银粉形貌从树枝状向球形转变,分散性能变佳.当PVP加入量为硝酸银的10％(质量分数)时,可制备出球形度高,分散性能较好,平均粒径为1.15 μm的超细银粉.通过调节PVP的添加方式能够实现超细银粉平均粒径在1.1～2.1 μm之间的可控制备.%Superfine Ag particles were prepared by liquid phase reduction method in the experiment with silver nitrate used as silver source,ascorbic acid as reductant and PVP as dispersant and protective agent,respectively.The influences of the dose and feeding method of PVP on the morphology,dispersity,and size of silver particles were investigated.The samples were characterized by scanning electron microscopy (SEM),X-ray diffraction (XRD) and laser particle sizer.The results show that with the increase of PVP dose in the reaction system,the morphology of Ag powders changes from mosssilver to spherical Ag particles,accompanied by a better dispersity.When the dose of PVP is 10％ (mass fraction) of silver nitrate,highly spherical silver particles are prepared with fine disersity,and the particle size is 1.15 μm.The particle size of superfine silver powder between 1.15 and 2.1 μm can be prepared controllably with the change of dispersant feeding method.