银纳米结构的固相合成及其光学、电化学性能

本文以硝酸银和抗坏血酸为原料,通过简单的室温固相路线快速合成了银纳米结构.TEM观察显示,表面活性剂对银纳米结构的形貌存在重要的影响:无任何表面活性剂存在时,只能获得团聚的银纳米粒子;十二烷基硫酸钠用作表面活性剂时,获得由银纳米粒子组装的纳米棒;而十六烷基三甲基溴化铵作表面活性剂时,可获得一些银纳米线.同时,不同的银纳米结构其光学、电化学性能也不相同:在UV-Vis光谱中,团聚的银纳米粒子的吸收峰位置分别在270nm和465nm;银纳米棒的吸收峰分别位置分别在284nm和442nm,且前者弱, 后者强;银纳米线则只在274nm处有一强的吸收峰.而在电化学响应中,团聚的银纳米粒子、纳米线和纳米棒的氧化、还原峰分别出现在0.396V和0.307V、0.087V和-0.045V、0.422V 和0.324V.

Solid-Phase Preparation and Optical, Electrochemical Properties of Silver Nanostructured Materials

A solid-phase route was used for fast preparation of silver nanostructures employing AgNO3 and VC (L-Ascorbic acid) as reactants. TEM observations showed that the aggregated Agnanoparticles were prepared in the absence of any surfactant; Ag nanorods were obtained when SDS was used and nanowires were produced in the presence of CTAB. The optical property of Agnanostructures was influenced by different surfactants. When no surfactant was used,two absorption peaks,a narrow one at 270 nm and a widened one centered at 465 nm,appeared in the UV-Vis absorption spectrum of the product; after CTAB was used,the two peaks shifted to 284n m and 442nm,respectively. Simultaneously,the former weakened and the latter enhanced; After SDS was used instead of CTAB,the widened peak badly weakened an d the narrow one at 274nm enhanced. Similarly,the electrochemical property of Ag nanostructures could be tuned by their shapes.