多面体纳米银粉的制备及表征

Preparation and characterization of polyhedral nano silver powder

采用液相化学还原法,以十六甲基溴化铵和聚乙烯吡咯烷酮为表面活性剂,以硼氢化钾直接还原硝酸银得到多面体银;将纳米银溶液经离心分离和真空干燥处理后制备出分散性好、形状规则的多面体纳米银粉;利用X射线衍射分析纳米银粉的晶体结构,利用粒度分析仪测试纳米银粉的粒径分布,利用X射线光谱仪分析纳米银粉的纯度,利用扫描电镜观察纳米银粉的形貌.研究结果表明,在80℃下,用十六甲基溴化铵（CTAB）做形貌诱导剂时,可制备出粒径为150~250nm的规则立方体形、面心立方晶系纯相的纳米银粉.

In this study,solution chemical reduction method was used to prepare polyhedral silver.To be specific,with cetyltrimethylammonium bromide（CTAB）and polyvinylpyrrolidone as surfactants,polyhedral silver was obtained from silver nitrate by direct reduction with potassium borohydride,and polyhedral nano silver powder with good dispersibility in regular shape was obtained after centrifugation and vaccum drying treatment of nano silver solution.Afterwards,the prepared nanometer silver powder was characterized by X-ray diffraction,X-ray spectrometer,granulometer,and scanning electron microscope（SEM）respectively for crystal structure,particle size distribution,fineness,and morphology.Results showed that with CTAB as the morphology inducer at 80 ℃,the obtained nanometer silver powder was uniform spherical shape and face-centered cubic（FCC）system with 150-250 nm in diameter.