Martín Alfonso, Schopf Carola, Pescaglini Andrea, Wang Jin Jin, Iacopino Daniela
Tyndall National Institute, Dyke Parade, Cork, Ireland.
Langmuir. 2014 Sep 2;30(34):10206-12. doi: 10.1021/la502195n. Epub 2014 Aug 20.
Droplet evaporation is a simple method to induce organization of Au nanorods into ordered superstructures. In general, the self-assembly process occurs by evaporation of aqueous suspensions under strictly controlled experimental conditions. Here we present formation of large area ordered vertical arrays by droplet evaporation of Au nanorod organic suspensions. The uncontrolled (free air) evaporation of such suspensions yielded to formation of ordered nanorod domains covering the entire area of a 5 mm diameter droplet. Detailed investigation of the process revealed that nanorods organized into highly ordered vertical domains at the interface between solvent and air on a fast time scale (minutes). The self-assembly process mainly depended on the initial concentration of nanorod solution and required minimal control of other experimental parameters. Nanorod arrays displayed distinct optical properties which were analyzed by optical imaging and spectroscopy and compared to results obtained from theoretical calculations. The potential use of synthesized arrays as surface-enhanced Raman scattering probes was demonstrated with the model molecule 4-aminobenzenthiol.
液滴蒸发是一种将金纳米棒组装成有序超结构的简单方法。一般来说,自组装过程是在严格控制的实验条件下通过水悬浮液的蒸发来实现的。在此,我们展示了通过金纳米棒有机悬浮液的液滴蒸发形成大面积有序垂直阵列的过程。这种悬浮液在不受控制(自由空气)的情况下蒸发,形成了覆盖直径5毫米液滴整个区域的有序纳米棒域。对该过程的详细研究表明,纳米棒在溶剂与空气的界面处快速(几分钟内)组装成高度有序的垂直域。自组装过程主要取决于纳米棒溶液的初始浓度,对其他实验参数的控制要求最低。纳米棒阵列表现出独特的光学性质,通过光学成像和光谱进行了分析,并与理论计算结果进行了比较。以模型分子4-氨基苯硫酚为例,证明了合成阵列作为表面增强拉曼散射探针的潜在用途。