纳米银枝晶的电沉积及结构表征

Electrodeposition and structural characterization of Ag nanodendrites

采用恒电位电沉积法,选择十二烷基磺酸钠(SDS)为表面活性剂,在Ti基体上制备了具有树枝状结构的纳米银。X-射线衍射试验表明银纳米枝状体为单晶结构,属于面心立方晶系。运用扫描电镜对枝晶的形貌特征进行观察分析,通过高分辨透射电子显微术对枝晶的晶格结构进行表征,发现枝晶表面由{111}晶面组成,主干和分支互成60°分别沿<110>方向生长,枝晶的{111}晶面形成多次孪晶结构。树枝状晶体形态的产生符合分形生长机理。

Nano-structured silver dendrite was obtained by potentiostatic electrodeposition in the presence of sodium dodecanesulphonate in aqueous solution using Titanium as substrate. X-ray diffraction （XRD） results showed that the as-prepared sample he longs to face-centered cubic structure. Morphology of the dendrite was characterized by scanning electron microscopy （SEM）. Structural information was revealed by high resolution transmission electron microscopy （HRTEM）. Results indicated that the dendrite is composed of （111 } exposed facets. The trunk-branching angles are 60°. The growth direction of the trunk and the branches are 〈110〉. Multi twins on { 111} planes were identified. It is suggested that the silver nanodendrites are formed by the aggregation of small particles as described by diffusion limited aggregation.