化学镀法合成纳米Ag包覆Al_2O_3复合粉

以平均直径约为200nm的Al2O3粉为原料,以氨基溶液为镀液,硝酸银为初始材料,在反应过程中,控制最佳的还原剂浓度、反应时间等参量,使Al2O3表面获得均匀的金属Ag涂层·以HRTEM,XRD,EDS等手段研究了化学镀银所获得的Ag Al2O3复合粉的结构·结果表明,所有的Ag Al2O3复合粉具有壳 核结构,壳层由纳米非晶银和纳米银晶体颗粒构成,尺度分别是5nm和10nm·

Synthesis of Ag-Cladding Al2O3 Powder by Chemical Deposition

The raw Al_2O_3 particles are 200 nm in average diameter. Chemical deposition of Ag was carried out taking ammonia-based solution as bath in which the silver nitrate is primary component. In the reaction process such parameters as the concentration of reducing agent, reaction time and others were optimized in order to clad uniformly all of Al_2O_3 particles. The result showed that all Ag-Al_2O_3 composite particles are of core-shell structure, of which the shell is composed of amorphous Ag and crystal Ag particles and their sizes are 5 nm and 10 nm respectively. The microstructures of Ag-cladding Al_2O_3 powder synthesized via silver chemical process was investigated by XRD, TEM and EDS techniques.