Island Growth in the Seed-Mediated Overgrowth of Monometallic Colloidal Nanostructures
Island Growth in the Seed-Mediated Overgrowth of Monometallic Colloidal Nanostructures
复制标题
种子介导的单金属胶体纳米结构过度生长中的岛生长
DOI：
10.1016/j.chempr.2017.08.004
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发表时间：
2017-10-12
期刊：
影响因子：
23.5
通讯作者：
Yin, Yadong
中科院分区：
文献类型：
--
作者：
Wang, Guoqing;Liu, Yiding;Yin, Yadong
控制胶体纳米晶体的生长模式具有重要的意义和技术意义，因为它通常与控制其形状、形态和物理化学性质有关。在传统观点中，薄膜沉积过程中的岛状生长仅限于晶格不匹配的材料。在这里，我们证明了在Au纳米结构(例如，纳米板、纳米棒和纳米球)上沉积Au可以在保持原始晶体结构的同时，在种子表面产生大小和密度可调的单独的Au岛。该体系中的岛状生长归因于快速氧化还原动力学和大分子配体表面封端的协同作用。降低反应速度或改变封端配体均可使Au在Au纳米结构上的沉积从岛状生长转变为逐层生长。我们进一步利用了板岛纳米结构致密的热点，并展示了它们在表面增强拉曼散射检测中的优势。
Manipulating the growth mode of colloidal nanocrystals is of both fundamental interest and technological importance because it is often connected to the control of their shape, morphology, and physicochemical properties. In conventional wisdom, island growth during thin-film deposition is restricted to lattice-mismatched materials. Here, we show that deposition of Au on Au nanostructures (e.g., nanoplates, nanorods, and nanospheres) can produce separate Au islands on the seed surface with tunable size and density while preserving the original crystal structure. The island growth in the system is ascribed to the synergistic effect of fast redox kinetics and surface capping of large polymeric ligands. Decreasing the reaction rate or changing the capping ligands could readily transform the deposition of Au on Au nanostructures from island growth to layer-by-layer mode. We further take advantage of the dense hotspots of the islands-on-plate nanostructures and demonstrate their excellence in surface-enhanced Raman scattering detection.