Immobilization of Cubic Silver Plasmonic Nanoparticles on TiO2 Nanotubes, Reducing the Coffee Ring Effect in Surface-Enhanced Raman Spectroscopy Applications
Immobilization of Cubic Silver Plasmonic Nanoparticles on TiO2 Nanotubes, Reducing the Coffee Ring Effect in Surface-Enhanced Raman Spectroscopy Applications
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DOI：
10.1021/acsomega.0c01356
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发表时间：
2020-06-16
期刊：
影响因子：
4.1
通讯作者：
Kudelski, Andrzej
中科院分区：
文献类型：
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作者：
Ambroziak, Robert;Krajczewski, Jan;Kudelski, Andrzej
通过将银立方纳米颗粒（Ag CNPs）固定在二氧化钛纳米管（TiO 2 NTs）上制备表面增强拉曼光谱（Sers）基底，用于研究“咖啡环”（CR）效应及其对测量的拉曼信号的空间再现性的影响，与平坦表面（Ti和Si）相比，其中CR效应通常是显著的。来自液滴的纳米颗粒的固定化是一种非常简单的技术，通常不允许沉积的NP均匀分布，因为在干燥区域的边界处存在材料的显著积累。我们提出的Sers基底通过使用有序的纳米结构有效地降低了CR效应，其中较少数量的Ag CNP被转移到边界区域。这不仅是表面形态是重要的，但也是TiO，NTs的物理化学性质，如润湿性。通过测量静态水接触角（WCA）来确定所制备的样品的润湿性，并使用俄歇电子能谱（Auger electron spectroscopy）来研究干燥区域边界附近的化学组成。使用扫描电子显微镜表征所获得的基板的形态。我们的研究表明，减少咖啡环效应增加了在沉积的CNP区域中测量的Sers信号的空间再现性。因此，所获得的平台可能在商业Sers应用中非常有用。
Surface-enhanced Raman spectroscopy (SERS) substrates prepared by immobilizing silver cubic nanoparticles (Ag CNPs) on titanium dioxide nanotubes (TiO2NTs) were used for investigations of the "coffee ring" (CR) effect and its impact on spatial reproducibility of measured Raman signals in comparison with flat surfaces (Ti and Si) where the CR effect is usually significant. The immobilization of nanoparticles from drops, which is a very simple technique, usually does not permit a homogeneous distribution of deposited NPs because there is significant accumulation of the material at the boundary of the drying area. Our proposed SERS substrates effectively reduced the CR effect through the use of well-ordered nanostructures where a smaller number of Ag CNPs were transferred to the boundary region. It was not only the surface morphology that was important but also the physicochemical properties of TiO, NTs, such as wettability. The wettability of the prepared samples was determined by measuring the static water contact angle (WCA), and the chemical composition near the boundary of the drying area was studied using Auger electron spectroscopy. The morphology of the substrates obtained was characterized using scanning electron microscopy. Our studies showed that reducing the coffee ring effect increased the spatial reproducibility of the measured SERS signal in the area of the deposited CNPs. Therefore, the platforms obtained may be very useful in commercial SERS applications.