Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63130, USA.
J Am Chem Soc. 2010 Jun 30;132(25):8552-3. doi: 10.1021/ja103655f.
This paper provides direct evidence to support the role of a capping agent in controlling the evolution of Ag seeds into nanocrystals with different shapes. Starting with single-crystal seeds (spherical or cubic in shape), we could selectively obtain Ag octahedrons enclosed by {111} facets and nanocubes/nanobars enclosed by {100} facets by adding sodium citrate (Na(3)CA) and poly(vinyl pyrrolidone) (PVP), respectively, as a capping agent while all other parameters were kept the same. This research not only offers new insights into the role played by a capping agent in shape-controlled synthesis but also provides, for the first time, Ag octahedrons as small as 40 nm in edge length for optical and spectroscopic studies.
本文提供了直接证据，支持了包覆剂在控制 Ag 种子演化为不同形状纳米晶体过程中的作用。从单晶种子（球形或立方体形）开始，通过分别添加柠檬酸钠（Na3CA）和聚乙烯吡咯烷酮（PVP）作为包覆剂，我们可以在保持其他参数不变的情况下，选择性地得到由{111}面封闭的八面体 Ag 和由{100}面封闭的纳米立方体/纳米棒。这项研究不仅为包覆剂在形状控制合成中所起的作用提供了新的见解，而且首次提供了小至 40nm 边长的八面体 Ag，可用于光学和光谱学研究。
