Sung Chia-Ling, Kao Tzung-Ta, Lin Yu-Cheng
Department of Engineering Science, National Cheng Kung University, Tainan 70101, Taiwan.
Institute of Photonics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 82445, Taiwan.
Nanomaterials (Basel). 2024 Sep 27;14(19):1562. doi: 10.3390/nano14191562.
This paper discusses the fabrication of three-dimensional dendritic Ag nanostructures, showcasing pronounced Localized Surface Plasmon Resonance (LSPR) effects. These nanostructures, employed in surface-enhanced Raman scattering (SERS), function as sensors for lactic acid in artificial sweat. The dendritic structures of the silver nanoparticles (AgNPs) create an effective SERS substrate, with additional hotspots at branch junctures enhancing LSPR. We achieve differential LSPR effects by varying the distribution and spacing of branches and the overall morphology. Adjustments to electrodeposition parameters, such as current and plating solution protective agents on an anodized aluminum oxide (AAO) base, allow for precise control over LSPR intensities. By pre-depositing AgNPs, the electron transmission paths during electrodeposition are modified, which leads to optimized dendritic morphology and enhanced LSPR effects. Parameter optimization produces elongated rods with main and secondary branches, covered with uniformly sized, densely packed, non-overlapping spherical AgNPs. This configuration enhances the LSPR effect by generating additional hotspots beyond the branch tips. Fine-tuning the electrodeposition parameters improved the AgNPs' morphology, achieving uniform particle distribution and optimal spacing. Compared to non-SERS substrates, our structure amplified the Raman signal for lactic acid detection by five orders of magnitude. This method can effectively tailor SERS substrates for specific analytes and laser-based detection.
本文讨论了三维树枝状银纳米结构的制备，展示了显著的局域表面等离子体共振（LSPR）效应。这些纳米结构用于表面增强拉曼散射（SERS），作为人工汗液中乳酸的传感器。银纳米颗粒（AgNP）的树枝状结构形成了有效的SERS基底，分支连接处的额外热点增强了LSPR。我们通过改变分支的分布和间距以及整体形态来实现不同的LSPR效应。调整电沉积参数，如电流和在阳极氧化铝（AAO）基底上的镀液保护剂，可以精确控制LSPR强度。通过预沉积AgNP，改变了电沉积过程中的电子传输路径，从而导致树枝状形态优化和LSPR效应增强。参数优化产生了带有主分支和次分支的细长棒，表面覆盖着尺寸均匀、紧密堆积且不重叠的球形AgNP。这种结构通过在分支尖端之外产生额外的热点来增强LSPR效应。微调电沉积参数改善了AgNP的形态，实现了颗粒分布均匀和间距优化。与非SERS基底相比，我们的结构将用于乳酸检测的拉曼信号放大了五个数量级。该方法可以有效地为特定分析物和基于激光的检测定制SERS基底。
