Murphy Catherine J, Sau Tapan K, Gole Anand M, Orendorff Christopher J, Gao Jinxin, Gou Linfeng, Hunyadi Simona E, Li Tan
Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, South Carolina 29208, USA.
J Phys Chem B. 2005 Jul 28;109(29):13857-70. doi: 10.1021/jp0516846.
This feature article highlights work from the authors' laboratories on the synthesis, assembly, reactivity, and optical applications of metallic nanoparticles of nonspherical shape, especially nanorods. The synthesis is a seed-mediated growth procedure, in which metal salts are reduced initially with a strong reducing agent, in water, to produce approximately 4 nm seed particles. Subsequent reduction of more metal salt with a weak reducing agent, in the presence of structure-directing additives, leads to the controlled formation of nanorods of specified aspect ratio and can also yield other shapes of nanoparticles (stars, tetrapods, blocks, cubes, etc.). Variations in reaction conditions and crystallographic analysis of gold nanorods have led to insight into the growth mechanism of these materials. Assembly of nanorods can be driven by simple evaporation from solution or by rational design with molecular-scale connectors. Short nanorods appear to be more chemically reactive than long nanorods. Finally, optical applications in sensing and imaging, which take advantage of the visible light absorption and scattering properties of the nanorods, are discussed.
这篇专题文章重点介绍了作者实验室在非球形金属纳米颗粒，特别是纳米棒的合成、组装、反应性及光学应用方面的工作。合成过程采用种子介导生长法，即在水中先用强还原剂还原金属盐，生成约4纳米的种子颗粒。随后在结构导向添加剂存在的情况下，用弱还原剂还原更多金属盐，可控制形成特定长径比的纳米棒，也能生成其他形状的纳米颗粒（星形、四足形、块状、立方体等）。金纳米棒反应条件的变化及晶体学分析有助于深入了解这些材料的生长机制。纳米棒的组装可通过溶液简单蒸发或利用分子尺度连接器进行合理设计来驱动。短纳米棒似乎比长纳米棒具有更高的化学反应活性。最后，还讨论了利用纳米棒可见光吸收和散射特性的传感与成像光学应用。
