Assembly of gold nanowires by sedimentation from suspension: Experiments and simulation.
Assembly of gold nanowires by sedimentation from suspension: Experiments and simulation.
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通过悬浮液沉降组装金纳米线：实验和模拟。
DOI：
10.1021/jp909251v
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
Fichthorn,KristenA
中科院分区：
文献类型：
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作者：
Triplett,DerekA;Quimby,LisaM;Smith,BenjaminD;Rodríguez,DarimarHernández;StAngelo,SarahK;González,Pedro;Keating,ChristineD;Fichthorn,KristenA
我们研究了金纳米线的排序，解决了从水悬浮液到玻璃基板上，由于重力。纳米线，CA。300 nm的横截面直径和ca.长度为2、4或7 μm，用2-巯基乙磺酸涂覆以提供静电排斥并防止聚集。使用光学显微镜从下方检查与衬底直接接触的纳米线层，发现其表现出近晶样有序。近晶有序的程度取决于纳米线的长度，最短（2 μm）的纳米线表现出最好的有序性。为了理解该系统中的组装，我们使用正则蒙特卡罗模拟来模拟衬底上纳米线的二维排序。我们考虑了纳米线之间的货车范德华力和静电相互作用。模拟再现了实验趋势，并表明，粗糙度的纳米线，局部增加静电排斥的两端，是正确预测实验观察到的近晶有序的关键。
We investigated the ordering of gold nanowires that settled from an aqueous suspension onto a glass substrate due to gravity. The nanowires, ca. 300 nm in cross-sectional diameter and ca. 2, 4, or 7 μm in length, were coated with 2-mercaptoethanesulfonic acid to provide electrostatic repulsion and prevent aggregation. The layer of nanowires in direct contact with the substrate was examined from below using optical microscopy and found to exhibit smectic-like ordering. The extent of smectic ordering depended on nanowire length, with the shortest (2 μm) nanowires exhibiting the best ordering. To understand the assembly in this system, we used canonical Monte Carlo simulations to model the two-dimensional ordering of the nanowires on a substrate. We accounted for van der Waals and electrostatic interactions between the nanowires. The simulations reproduced the experimental trends and showed that roughness at the ends of the nanowires, which locally increased electrostatic repulsion, is critical to correctly predicting the experimentally observed smectic ordering.