Department of Chemistry, and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
J Am Chem Soc. 2013 Mar 13;135(10):3800-3. doi: 10.1021/ja400794q. Epub 2013 Mar 1.
The direct growth of planar-twinned Au nanoparticles (NPs) in high yield remains a challenge in shape-controlled NP synthesis largely because suitable planar-twinned seeds for Au NP growth have not been identified to date. Herein we describe the use of planar-twinned Ag triangular nanoprisms as a means to dictate Au NP twin structure. In a one-pot process, the Ag triangular nanoprisms first undergo oxidative Au replacement, forming Ag-Au alloy nanoframes and concomitantly releasing Ag(+) into solution, which then directs subsequent Au NP growth through an underpotential deposition process. The planar-twinned structure of the initial Ag nanoprism is maintained throughout particle growth. Using this method, we have successfully synthesized Au hexagonal bipyramids in high yield for the first time.
平面孪晶 Au 纳米颗粒（NPs）的大量直接生长仍然是形状控制的 NP 合成中的一个挑战，主要是因为到目前为止还没有确定合适的平面孪晶种子用于 Au NP 生长。在此，我们描述了使用平面孪晶 Ag 三角纳米棱柱作为控制 Au NP 孪晶结构的一种手段。在一锅法中，Ag 三角纳米棱柱首先经历氧化 Au 置换，形成 Ag-Au 合金纳米框架，并同时将 Ag(+)释放到溶液中，然后通过欠电位沉积过程指导随后的 Au NP 生长。初始 Ag 纳米棱柱的平面孪晶结构在整个颗粒生长过程中得以保持。使用这种方法，我们首次成功地以高产率合成了 Au 六方双锥。
