摘要
系统研究了以抗坏血酸为还原剂制备亚微米级球形单分散银钯合金粉的工艺.发现分散剂浓度和体系pH值对银钯粉的尺寸形貌影响很大.当pH为2时,银钯离子电位差为零,可同时被还原,所得颗粒均匀,合金化程度最高.随着分散剂浓度降低,颗粒间空间位阻减小,颗粒尺寸增大,团聚加剧.在pH为2时,分散剂和氧化剂质量比为0.1∶1条件下得到的粉体,经过500℃煅烧,制得的颗粒呈球型,表面光滑,分散性好,平均粒径为300～600 nm,且具有较高的合金化程度.
In this work,the synthesis of sub-micrometer sized spherical silver-palladium alloy powders using ascorbic acid as the reductant was investigated.It was found that the concentration of the dispersant and the pH of the reaction solution have great effects on the morphology of the silver-palladium powder.The result indicates that silver-palladium particles synthesized at the pH value of 2 have uniform grain size and good alloying constitution due to the simultaneous reduction of nitrate silver and nitrate palladium because of their equal potential.With the decrease of dispersant concentration,the particles tend to grow into larger size and become seriously agglomerated.After calcining at 500 ℃,spherical silver-palladium particles 200 to 600 nm in size and with good dispersion and alloy constitution can be obtained.
出处
《材料与冶金学报》
CAS
北大核心
2013年第2期124-127,131,共5页
Journal of Materials and Metallurgy
基金
稀贵金属综合利用新技术国家重点实验室开放课题资助
关键词
银钯合金粉末
化学还原
亚微米级
球形
silver-palladium alloy powder
chemical reduction
sub-micrometer
spheres
