【作者】 李迪； 齐利民；

【Author】 Di Li;Limin Qi;College of Chemistry and Molecular Engineering,Peking University;

【机构】 北京大学化学与分子工程学院；

【摘要】 纳米摇铃结构是一种具有内部空腔的特殊核壳结构,通常由一个外壳和一个可移动内核组成,它因独特的结构和性质而受到人们的广泛关注。最近,我们组报道了具有特殊凹形结构的箭头状金纳米粒子的可控合成[1]。在本工作中,我们以这种独特的金纳米箭头(GNA)作为核,通过溶液中的化学沉积和Galvanic置换反应[2],可控制备了新颖的GNA@Ag纳米核壳结构和GNA@AuAg纳米摇铃结构。在水溶液中通过调控表面活性剂的浓度和硝酸银的添加量,可以在金纳米箭头的表面包覆不同厚度的银层,分别得到箭头形和长方体形的GNA@Ag核壳纳米粒子。随后以不同厚度银层包覆的GNA@Ag核壳纳米粒子作为种子,利用Galvanic置换反应结合共还原过程,便可得到不同形貌且具有不同纳米间隙结构的GNA@AuAg纳米摇铃结构(图1)。该纳米摇铃结构具有独特的等离激元共振性质,呈现出可调的光吸收性质和优异的表面增强拉曼散射(SERS)性能。更多还原

【Abstract】 Nanorattles composed of an outer shell and a movable inner core have attracted considerable attention owing to their unique structure and properties. Recently, our group reported the synthesis of uniform gold nanoarrows(GNAs) consisting of two pyramidal heads connected by a four-wing shaft. In this work, uniform GNA@Ag core-shell nanoparticles and novel GNA@AuAg nanorattles were successfully fabricated by chemical deposition coupled with Galvanic replacement using the GNAs as the seeds. Firstly, arrow-shaped and cuboidal GNA@Ag core-shell nanoparticles were obtained by adjusting the concentration of the surfactant and the amount of silver nitrate. Subsequently, various GNA@AuAg nanorattles with diverse structures and different nanogaps were obtained through Galvanic replacement. The novel GNA@AuAg nanorattles exhibited tunable plasmonic absorption and excellent performance in surface-enhanced Raman scattering(SERS) due to their special structures.更多还原